Atomic vacancies in semiconductor materials are usually considered detrimental due to their role in trapping photogenerated carriers, leading to attenuated crystallinity and poor photoelectric conversion efficiency. However, the deliberate and controlled introduction of atomic vacancies within an optimal ratio range in semiconductor photocatalysts can significantly improve their catalytic efficiency. Specifically, vacancy sites can optimize the electronic configuration, promote charge carrier separation, activate reactant molecules, lower activation energies, and improve visible light harvesting, thereby enhancing photocatalytic performance. In this review, we systematically highlight the multiplicity of vacancies in semiconductor materials and examine their innovative role in driving photochemical solar fuel and high-value chemical production. An in-depth discussion of the underlying photoreaction mechanisms associated with the vacancy-mediated process is firstly elaborated, followed by introducing the advanced characterizations employed to uncover the merits of vacancies as well as currently developed strategies for vacancy-engineering in photocatalysts. Next, the current advances in utilizing vacancy contained photocatalysts for photochemical solar fuel and value-added chemical production are discussed and appraised, putting emphasis on their applications in water splitting, CO₂ conversion, H₂O₂ generation, and N₂ fixation. With the opportunities and challenges in this field, we concluded by presenting an outlook on the further prospects and key issues for the practical application of vacancy contained semiconductor materials. We sincerely hope that this review can spur new concepts to advance industrial-scale solar fuel and value-added chemical generation using vacancy-engineered semiconductor photocatalysts.

Fischer-Tropsch synthesis converts syngas (CO/H₂) to liquid fuels and value-added chemicals, but conventional thermocatalysis requires severe conditions, shows rapid deactivation, and offers limited control over product distributions. This review examines photo-driven Fischer-Tropsch synthesis with a focus on advances reported in the past decade, concentrating on two mechanistic routes: photo-induced thermal catalysis and photothermal synergistic catalysis. We compile progress in materials design that includes support and interface engineering, modulation of the active phase, and rational use of cocatalysts. Pathway control is discussed with emphasis on lowering methane and carbon dioxide formation while steering selectivity to C₂₊ olefins or C₅₊ alkanes under comparatively mild conditions. By contrasting the two routes, the review clarifies differences in energy transduction and the roles of photogenerated charge carriers, and from these differences extracts general principles for selectivity engineering and catalyst stability. Critical gaps are identified, notably quantitative separation of thermal and non-thermal effects, operando elucidation of reaction intermediates, standardized reporting of light and temperature, and long-term durability under realistic feeds. The review closes with research priorities for coupling mechanism-informed catalyst design with thermal management and reactor scale strategies to advance Fischer-Tropsch synthesis toward application.

We develop a Ni-Cu dual single-atom catalyst (DSAC) as a model catalyst to investigate the neighboring synergy in dual single-atom sites for promoting the electrocatalytic carbon dioxide reduction reaction (ECO₂RR) kinetics. Through detailed electrochemical tests, in situ spectroscopic observations and theoretical calculations, we found that during ECO₂RR, the neighboring Ni-Cu dual single-atom sites synergistically weaken the rigidity of the hydrogen-bond networks of interfacial water and optimize the spatial configuration of water molecules surrounding the Ni-Cu dual single-atom sites, which increases the proportion of easily dissociated water species in the interfacial water, thus accelerating the CO₂ protonation kinetics during the conversion of CO₂ to CO. As a result, Ni-Cu DSAC exhibits a 1.5-fold increase and a 15-fold increase in ECO₂RR activity compared to Ni SAC and Cu SAC, respectively. In flow cell electrolyzer, Ni-Cu DSAC achieves almost 100% Faradaic efficiency for CO production (FE_CO) from applied current density of 50 to 400 mA cm⁻², with the optimal full-cell energy efficiency of 61.1% for CO production, reflecting the excellent catalytic performance of neighboring Ni-Cu dual single-atom sites for selective conversion of CO₂ to CO. Benefiting from the efficient suppression of carbonates formation in acidic media, Ni-Cu DSAC achieves an outstanding single-pass carbon efficiency of 67.3% for CO₂-to-CO conversion at 200 mA cm⁻². Additionally, Ni-Cu DSAC also exhibits excellent long-term stability, with less than 10% decay of FE_CO throughout a 170-h continuous electrolysis in strong acid (pH = 1, j = 200 mA cm⁻²).

Asymmetric electron distribution at single-atom centers offers a promising pathway to enhance photocatalytic CO₂-to-CO conversion; however, direct visualization of how such symmetry-breaking influences local electric fields and reaction coordinates remains elusive. Herein, an asymmetric N-Ru-S motif was constructed in a thiophene-based covalent organic framework (Ru/Py-bTDC) via post-synthetic metalation. Under visible light in a gas-solid system without sacrificial agents, Ru₁₀/Py-bTDC exhibited a CO production of 226.88 μmol·L^-1, representing a 13-fold increase over pristine Py-bTDC. In-situ Kelvin probe force microscopy revealed that the N-Ru-S unit acts as a directional nanoscale dipole, intensifying the internal electric field (IEF) by 6.15-fold and steering photogenerated electrons toward Ru sites to facilitate charge separation. In-situ Fourier transform infrared spectroscopy and theoretical calculations demonstrated that the enhanced IEF promotes CO₂ activation, lowering the energy barrier for *COOH formation from 2.63 to 0.40 eV and shifting the rate-determining step to *CO desorption. This work establishes a direct spatial correlation between atomic-scale asymmetry, IEF enhancement, and optimized reaction kinetics, offering a design strategy to overcome both charge separation and activation barriers in CO₂ photoreduction through symmetry-breaking coordination.

The selective conversion of CO₂ into value-added chemicals remains a critical challenge in heterogeneous catalysis. Here, we demonstrate that reaction pressure governs a decisive mechanistic switch in CO₂ hydrogenation over potassium-promoted iron catalysts. Catalytic tests conducted from 0.1 to 10.0 MPa reveal that moderate pressure (3.5 MPa) favors Fischer-Tropsch-type pathways, yielding long-chain hydrocarbons through Fe₅C₂-mediated C-C coupling. In contrast, elevated pressures (≥ 7.0 MPa) suppress hydrocarbon formation and promotes the production of long-chain oxygenates, including higher alcohols and carboxylic acids. Comprehensive structural characterization indicates a clear pressure-dependent phase transformation: Fe₅C₂ progressively diminishes and evolves into FeCO₃, accompanied by increased Fe-O and carbonate surface species. Operando diffuse reflectance infrared Fourier transform spectroscopy reveals that FeCO₃-rich surfaces stabilize COO-containing intermediates and inhibit C-O bond scission, favoring direct COO insertion rather than Fischer-Tropsch chain growth. CO-temperature programmed surface reaction further confirms that FeCO₃ is catalytically inert toward CO activation, explaining the reduced CO₂ conversion observed at high pressure. The combined results establish FeCO₃ as a pressure-generated phase that redirects CO₂ hydrogenation from hydrocarbon-selective to oxygenate-selective pathways. This work provides mechanistic insight into pressure-driven catalyst restructuring and offers a new strategy for tuning oxygenate selectivity in CO₂ hydrogenation.

The development of photo-switchable CO₂ reduction catalysts capable of selectively generating two distinct target products under different light irradiation holds significant potential for achieving multifunctional catalysis and enhancing economic viability in industrial applications, yet remains a formidable challenge. Herein, we demonstrate a hollow core-shell plasmonic TiO₂/AuCu@TB-COF (TACT) photocatalyst that achieves 343.9 μmol g_cat^-1 h^-1 activity and 98.7% selectivity toward CH₄ under ultraviolet (UV) light, but switches to 132.7 μmol g_cat^-1 h^-1 activity with 86.6% selectivity for CO under visible light in pure water without altering any other reaction conditions. Comprehensive mechanistic studies reveal that UV and visible light selectively excite different components, inducing distinct interfacial charge transfer routes. This not only endows TACT with higher charge separation efficiency under UV light versus visible light, but also directs photocarriers to different active sites for redox reactions depending on the irradiation wavelength. Specifically, H₂O oxidation occurring on the TiO₂ core under UV light more favorably promotes O₂ evolution and proton liberation compared to oxidation on the TB-COF shell under visible light. For CO₂ reduction, UV light drives consecutive hydrogenation of *CO intermediates on the AuCu sites, whereas visible light preferentially induces *CO desorption from the TB-COF surface. The contrasting electron and proton supply, combined with the divergent fates of *CO intermediates, collectively govern the wavelength-dependent CO₂ reduction pathways.

In recent years, metal-organic frameworks (MOFs) based materials have garnered significant interest for photocatalytic CO₂ reduction, owing to their unique structural features coupled with exceptional CO₂ capture capacities. Due to the insufficient light absorption capacity and low efficiency of photogenerated electron-hole separation, their catalytic activities still need to be further improved. Plasma cocatalyst is considered as a promising strategy to expand light absorption range and facilitate separation efficiency of photogenerated charges for inorganic semiconductor photocatalysts, thereby also beginning to be explored and applied in the MOFs-based photocatalysts. However, due to the usual lattice mismatch or large growth differences between metals and MOFs, interface barriers exist, which to some extent hinders the effective transmission of photogenerated electrons. Build-in electric field (IEF) of the interface could be used as the driving force to overcome the interface barriers, promoting the transfer of charge carriers. Herein, the non-noble metal Bi and ordinary MIL-125 are chosen as plasma cocatalyst and MOF object, respectively, forming Bi/MIL-125 composite via an in-situ reduction strategy. The experimental results and theoretical calculation demonstrate that an IEF is formed and pointed from Bi to MIL-125. And metal Bi possesses obvious plasma light absorption and carrier capture capabilities. Built-in electric field in coordination with Bi plasma co-catalytic effect realizes the highly efficient photocatalytic CO₂ reduction. The optimized BM-110 demonstrates a 10.4-fold higher CO production rate relative to the initial MIL-125, recording a yield of 96.63 µmol g^‒1 h^‒1. This work demonstrated a new insight to design MOF-based photocatalysts for photocatalytic CO₂ reduction.

Ni-based catalysts have shown significant potential in CO₂ methanation, but the high catalytic performance is usually obtained at quite high Ni loading, as small particles just transform CO₂ into CO via reverse water gas shift reaction. Thus, a scientifically and practically important work is clarification of the structure of the smallest active Ni species and the catalytic activity of structurally different Ni species. Here, MnO_x-modulated metallic nickel dimers (MnO_x-Ni₂) were embedded in silicalite-1 framework at a Ni loading of ~0.86%. It’s CO₂ conversion, CH₄ selectivity and CH₄ space time yield (STY) surprisingly reach ~76%, ~98% and ~450 mol·mol_Ni^-1·h^-1 at 400 °C, 0.5 MPa and 12000 mL·g^-1·h^-1. Such a catalytic performance can be well maintained at least within 200 h. In-situ spectroscopy, density functional theory (DFT) calculation and ab initio molecular dynamics simulation results confirm that Ni dimer (Ni₂) is the smallest Ni cluster triggering the CO₂ methanation and the CH₄ formation activity is linearly increased with the Ni₂ content. Introduction of MnO_x not only increases the number of Ni₂ species, but also improves its intrinsic activity in CO₂ methanation, as MnO_x enhances the electronic density of Ni species and facilitates NiO reduction to MnO_x-Ni₂ species. This species shows higher H₂ dissociation activity than single atom Ni (Ni₁), pure Ni₂ and large Ni nanoparticles (NPs). In addition, it exhibits much stronger CO adsorption and lower energy barrier of CO* intermediate hydrogenation to CH₄. In-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), isotope-labeled in-situ DRIFTS, on line mass spectroscopy (MS), Proton transfer reaction time of flight PTR TOF-MS and DFT calculation results reveal that CO₂ hydrogenation to methane on MnO_x-Ni₂@MFI mainly follows the HCOO* and CO* intermediates route.

The efficacy of photocatalytic pollutant degradation is fundamentally governed by charge carrier separation dynamics and redox potential preservation. To address these critical factors, we developed a plasmon-enhanced Ag/AgBr/C₃N₅ S-scheme heterojunction through a facile assembly approach. Systematic characterization and theoretical calculations reveal the establishment of a robust interfacial electric field that simultaneously promotes efficient charge separation while maintaining the strong inherent redox capabilities of individual components. The incorporation of plasmonic Ag nanoparticles introduces localized surface plasmon resonance, significantly broadening visible light absorption and generating energetic hot electrons. This synergistic integration of S-scheme charge transfers and plasmonic effects contributes to reinforced production of reactive species and yields exceptional photocatalytic performance, achieving 87.9% degradation of levofloxacin within 50 min under visible light irradiation. This performance surpasses those of pristine AgBr, AgBr/C₃N₅ and C₃N₅ by factors of approximately 1.76, 1.35 and 11.2, respectively. Mechanistic investigations through intermediate analysis elucidate a plausible levofloxacin degradation process, while eco-toxicological assessments confirm the environmentally benign nature of the final products. This work establishes a novel design paradigm for designing plasmon-enhanced S-scheme photocatalysts, offering a sustainable solution for antibiotic remediation in aqueous systems.

Light-driven synthesis of hydrogen peroxide (H₂O₂) presents an ideal pathway for sustainability as compared to the traditional anthraquinone process. Herein, we introduce a strategic approach for functionalizing poly(heptazine imide) with triazole groups via a one-step calcination process using alkali-metal salts (NaCl/KCl/LiCl). Featuring a donor-acceptor framework that promotes singlet electron dissociation, the optimal catalyst (KNa) displayed outstanding photocatalytic performance, achieving H₂O₂ production at 9.32 mmol L^-1 h^-1 and benzaldehyde (BAD) generation at 8.14 mmol L^-1 h^-1. KNa reached an apparent quantum efficiency of 11.58% at 420 nm, in the absence of noble-metal cocatalysts. It also exhibited an electron-hole utilization close to unity (89%), indicating its efficiency in driving photoredox reactions. Mechanistic studies conducted through electrochemical measurements and scavenger tests revealed that KNa facilitated a 2-electron pathway for H₂O₂ production, with photogenerated charges and radicals (electron, hole, O₂^•-, ¹O₂) participating in the reaction. A shift in electron density and enhanced O₂ adsorption observed from computational analysis reflects the donor-acceptor effect of the terminal triazole units on PHI. The versatility of KNa for other photochemical reactions was also exemplified by its simultaneous generation of H₂O₂ (1.11 mmol L^-1 h^-1) and furfuraldehyde (0.75 mmol L^-1 h^-1). As such, this research paves an in-depth understanding of synergistic dual-functional photocatalysts for photoredox reactions.

Harnessing solar energy as a power source for sustainable fuel production from biomass waste presents an effective solution to energy and environmental challenges. However, efficient utilization of low-energy near-infrared (NIR) light (representing ~50% of solar irradiance) continues a critical bottleneck especially for non-edible oils valorization. Here, we report a cellulose-derived sulfonated hydrochar (PC-SO₃H-1) utilizing the full solar spectrum for highly efficient biodiesel production, achieving a remarkable biodiesel yield of 98.29% within only 30 min, which far exceeds the theoretical limit. Favorable NIR absorption of narrow bandgap PC-SO₃H-1 combined with substrate adsorption capacity enhanced by -SO₃H functionalization overcomes thermodynamic equilibrium limitations. The optimized charge transfer dynamics accelerate the interfacial localized photothermal effect, driving the esterification reaction forward while minimizing heat loss and significantly enhancing the utilization of NIR photons. Density functional theory calculations demonstrate the formation of crucial intermediate ester carbonyl groups (C=O), with PC-SO₃H-1 effectively reducing the activation energy barrier associated with the rate-limiting process. This sustainable noble metal-free photothermal catalytic system of high-efficiency overcomes the reliance of traditional photocatalysis on high-energy photons, offering novel insights into the full spectrum solar-driven production of green and renewable biofuels.

Photocatalytic hydrogen peroxide (H₂O₂) generation from water and air provides a prospective means for converting solar energy into valuable chemicals, which, however, is limited by the low carrier separation efficiency of traditional single-component semiconductor photocatalysts. Herein, we report a facile strategy for constructing an S-scheme organic heterojunction by integrating graphitic carbon nitride (g-C₃N₄) with covalent triazine frameworks (CTFs). The thiadiazole-modified CTFs are precisely functionalized with benzothiadiazole, phenyl, and biphenyl groups. The hybrid with optimized structure achieves a 3259 μmol g⁻¹ h⁻¹ H₂O₂ generation rate, outperforming pristine CTFs and g-C₃N₄ by 78-fold and 8-fold, respectively. In-situ characterizations confirm the enhanced light absorption, redox capacity, and charge carrier dynamics of the g-C₃N₄/CTF S-scheme heterojunction. The thiadiazole units increase active sites within CTFs and collaborate with g-C₃N₄ to accelerate electron-hole separation and enable high H₂O₂ selectivity. Through theoretical/experimental analyses, the O₂ adsorption configuration on CTFs is revealed to favor a two-step single-electron O₂ reduction route, reducing thermodynamic barriers for O₂-to-H₂O₂ conversion. Providing design strategies for organic heterojunctions with enhanced electronic structures, this study enables efficient artificial H₂O₂ photosynthesis.

Photocatalytic hydrogen production coupled with value-added chemical synthesis has attracted extensive research interests as a promising route to realize efficient conversion of solar energy to chemical energy. However, the rapid charge recombination hinders the improvement of conversion efficiency. Herein, a pyrene-based conjugated polymer (PyDF)/Mn_0.2Cd_0.8S (MCS) organic-inorganic S-scheme heterojunction photocatalyst (PMCS) was reported. The incorporation of large delocalized π-conjugation system and formation of the S-scheme heterojunction significantly enhanced the charge separation and transfer. As a result, the optimal PMCS_0.5 composite exhibited a hydrogen evolution rate of 16.3 mmol h^-1 g^-1 with ascorbic acid as sacrificial agent. In the coupled system for benzylamine (BA) oxidation and hydrogen production, it delivered a hydrogen evolution rate of 3.72 mmol h^-1 g^-1, with nearly 100% conversion of 358.8 μmol BA to N-benzylidene benzylamine (NBBA) within 4 h. To elucidate the charge transfer mechanism within the S-scheme heterojunction, density functional theory calculations, in-situ X-ray photoelectron spectroscopy, and in-situ irradiated Kelvin probe force microscopy were conducted. In addition, in-situ diffuse reflectance infrared Fourier transform spectroscopy was employed to monitor the stepwise transformation of amines to imines during the photocatalytic process. This work offers a promising approach for bifunctional photocatalyst design toward simultaneous energy conversion and green synthesis.

Water is an ideal hydrogen or oxygen source in chemical synthesis. However, many organic reactions are unable to utilize this potential or even incompatible with aqueous conditions. Here, we report a synergistic visible light organophotoredox Co-catalyzed highly regio- and stereoselective hydroxymethylation of alkynes with N-methylamines and water. This method employs water as both hydrogen (H) and oxygen (O) donor, with N-methyl trialkylamines serving as C1 synthon and photoredox reductant, thereby eliminating exogenous oxygenated C1 reagents. A variety of tri-substituted allylic alcohols have been obtained with excellent regio- (up to >19:1 rr) and stereoselectivity (> 19:1 E/Z for over 30 examples). Mechanistic studies reveal two critical water assistant processes involving selective C-N cleavage of N-methylamines generating formaldehyde and subsequent regioselective reductive hydroxymethylation of alkynes via photoredox cobalt dual catalysis.

Covalent organic frameworks (COFs) unveil exceptional potential for selective photocatalysis, owing to their molecularly tunable structures. Herein, four COFs are designed with vinylene-linked isomeric thienothiophenes. Thereby, the condensation of 4,7-bis(2,6-dimethylpyridin-4-yl)benzo[c] [1,2,5]thiadiazole (MPBTD) and 4,7-bis(2,6-dimethylpyridin-4-yl)benzo[c][1,2,5]oxadiazole (MPBO) with thieno[3,2-b]thiophene-2,5-dicarbaldehyde (T32T) and thieno[2,3-b]thiophene- 2,5-dicarbaldehyde (T23T) yields MPBTD-T32T-COF, MPBTD-T23T-COF, MPBO-T32T-COF, and MPBO-T23T-COF, respectively. Comprehensive characterizations and theoretical calculations confirm the well-defined crystalline porous structures and distinct optoelectronic properties of these four COFs. Notably, the electron-withdrawing units, benzo[c][1,2,5]thiadiazole and benzo[c][1,2,5]oxadiazole, tweak the electron push-pull effect of COFs, leading to distinct photocatalytic performances. In the selective photocatalytic oxidation of three sulfide substrates, the observed performance exhibits the following order: MPBTD-T32T-COF > MPBTD-T23T-COF > MPBO-T32T-COF > MPBO-T23T-COF. Mechanistic studies reveal that superoxide is the predominant reactive oxygen species powering the selective photocatalytic sulfoxidation over MPBTD-T32T-COF. Furthermore, MPBTD-T32T-COF demonstrates recyclability and broad substrate applicability for the selective photocatalytic sulfoxidation.

The development of efficient and stable visible-light-driven Z-scheme systems for overall water splitting was crucial for solar hydrogen production. However, performance was often limited by photocorrosion of sulfide-based hydrogen evolution photocatalysts and competing, deactivating side reactions involving the redox shuttle. Herein, we construct a robust Z-scheme system by employing a CoP-modified Ni-doped Zn_0.5Cd_0.5S heterojunction with strong interfacial interaction as the HEP, coupled with BiVO₄ as the oxygen evolution photocatalyst. The optimized system exhibited an apparent quantum yield of 4.06% at 420 nm and enabled sustained co-evolution of hydrogen and oxygen at a near-stoichiometric ratio. It also demonstrated outstanding cycling stability. Crucially, it had been demonstrated that the regulation of the internal polarizability of HEP effectively suppressed the competitive reduction of the redox medium and the formation of passivated Prussian blue derivatives on the catalyst surface. This work provides fundamental insights into mitigating the side effects caused by fusion through polarizability regulation.

The widespread deployment of proton exchange membrane fuel cells is hindered by the “catalysis trilemma” of the oxygen reduction reaction (ORR), which demands simultaneous high activity, exceptional durability and low cost. To overcome this longstanding bottleneck, we propose a universal tungsten nitride (WN) enhanced metal-N-C platform, where WN synergizes with metal-N_x sites to create a robust and electronically modulated support for Pt catalysts. This dual-anchoring and synergistic-catalyzing architecture not only effectively suppresses Pt nanoparticle migration and dissolution but also optimizes Pt activity, thereby accelerating ORR kinetics and enhancing structural integrity. As a prototypical example, the Pt/WN-Fe-N-C catalyst delivers a remarkable peak power density of 1.85 W/cm² at an ultralow cathode Pt loading of 0.05 mg-_Pt/cm² and retains 91.1% peak power density after 90000 accelerated durability test cycles with 4 mV voltage loss at 0.80 A/cm²-significantly exceeding the U.S. DOE 2030 targets. This work establishes a generalizable materials design strategy to break the activity-stability-cost trade-off in fuel cell catalysis.

Electrocatalysis is a green alternative to directly synthesize cyclohexanone oxime (CHOX, Nylon-6 precursor) via electrocatalytic reduction of nitrogen oxides to NH₂OH and spontaneous C-N coupling with cyclohexanone, but suffering from a low-yield or poor Faradaic efficiency (FE) because of the scaling relationship. Herein, a strategy of heteroatom-doping-regulated oxygen vacancies (Vo) engineering was proposed to design a robust Cu-ZnO_1‒x catalyst for efficient electrosynthesis of cyclohexanone oxime (ESCO). The complete characterizations and theoretical studies revealed that the doped-Cu can reduce Vo sites formation energy and regulate their local electronic state. The synergistic effect between doped Cu and Vo led to the break of the scaling relationship, presenting the enhancement of NO₃^- adsorption/dissociation, the weakness of H* adsorption, and the balance of the NH₂OH adsorption for further C-N coupling reaction. Therefore, the hydrogen evolution reaction and NH₂OH reduction to NH₃ side reactions can be suppressed. The optimized Cu-ZnO_1‒x delivered an outstanding activity with a 1238.8 μmol h^‒1 mg_cat.^‒1 yield and 68.2% FE. Lastly, the reaction mechanism was established following *NO₃ → *NO₃H → *NO₂ → *NO₂H → *NO → *HNO → *NHOH → *NH₂OH and spontaneous C-N coupling with cyclohexanone to form CHOX. The outstanding ESCO performance on Cu-ZnO_1‒x catalyst demonstrates the effectiveness of this heteroatom-doping-regulated Vo engineering strategy.

Seawater electrolysis integrated with renewable energy sources represents a green and sustainable pathway for hydrogen production, yet its practical application is severely constrained by the lack of cost-effective, highly active, and scalable electrodes. Herein, we report the construction of a high-performance hydrogen evolution reaction (HER) electrode by engineering the local-atomic environment of Ni sites through vanadium oxide modification. This optimized electrode delivers current densities of 500/1000 mA cm^-2 at only 283/361 mV in alkaline seawater. Impressively, a kW-scale alkaline seawater electrolyzer achieves continuous operation at an industrial-level current up to 25 A for over 880 h with an ultra-low degradation rate of 34.1 μV h^-1. Combined experimental and theoretical investigations reveal a volcano-type relationship between the chemical state of Ni and the adsorption energy of the key intermediate H* (∆G_H*), as well as the potential of zero charge (PZC) of the electrode. Furthermore, in-situ Fourier-transform infrared spectroscopy confirms that a lower PZC promotes the formation of more free water molecules near the electrode surface, thereby facilitating the HER process. This work uncovers atomic environment-governed HER mechanisms and develops a scalable, industrially stable seawater electrolysis electrode, bridging lab-innovation to practical hydrogen production.

Electrocatalytic nitrogen reduction reaction (NRR) under ambient conditions offers a sustainable alternative to the energy-intensive Haber-Bosch process. However, the two canonical catalytic pathways face intrinsic limitations: the alternating mechanism suffers from high *NH₂NH₂ desorption losses, while the distal pathway requires prohibitive activation energy for N₂ protonation. The simultaneous realization of high activity and selectivity thus remains a critical challenge. Here, we demonstrate that boron doping modulates the electronic structure of Mo₂TiC₂T_x/MoO₂ by upshifting the d-/p-band center toward the Fermi level, unveiling the dominant a hybrid “distal-alternating” pathway that favors the *NNHH → *NHNH₂ transition rather than the *NNHH → *N cleavage. In addition, the electron-deficient B sites weaken the binding affinity toward Lewis-acidic protons under acidic conditions, thereby effectively suppressing the competing hydrogen evolution reaction. Significant interfacial charge transfer from MoO₂ to the B@Mo₂TiC₂T_x surface further ensures a sufficient electron supply for N₂ activation and stepwise hydrogenation. As a result, B@Mo₂TiC₂T_x/MoO₂ delivers an impressive ammonia yield of 121.18 μg h^‒1 mg_cat.^‒1 with a Faradaic efficiency of 75.94% at a mild potential of -0.2 V vs. RHE. This work unveils the mechanistic feasibility of a non-classical hybrid NRR pathway and establishes a rational strategy for designing next-generation high-efficiency nitrogen reduction electrocatalysts.

Persistent proton accumulation from extensive reactant deprotonation during oxygen evolution reaction (OER) induces severe local acidification at electrode-electrolyte interface, accelerating catalyst degradation and performance decay. Employing NiFe layered double hydroxide (NiFe-LDH) as a model, we present a bioinspired strategy wherein Lewis-basic acetate anion (CH₃COO^-, Ac^-) functions as dynamic proton shuttle to regulate interfacial microenvironment (Ac^--LDH). Ac^- undergoes reversible -COO^-/-COOH cycle upon protonation, promoting efficient proton transfer and reinforcing hydrogen-bond networks that expedite OH^- delivery to LDH surface. Simultaneously, Ac^- lone pairs selectively coordinate with Fe centers in LDH framework, tuning electronic structure and enhancing intrinsic activity. In-situ Raman and infrared spectroscopy capture transient CH₃COOH formation, while differential electrochemical mass spectrometry evidences proton shuttling via CH₃COOD detection. Theoretical calculations reveal that Ac^- coordination stabilizes active site and reduces OER energy barrier. Leveraging this dual functionality, Ac^--LDH exhibits superior activity with 213 mV overpotential at 10 mA cm^-2 and remarkable durability, maintaining 50 mA cm^-2 for over 1200 h in anion-exchange membrane electrolyzer. This work establishes bioinspired molecular shuttles for interfacial microenvironment engineering as versatile paradigm for developing OER catalysts with high activity and durability.

Seawater electrolysis, while promising for sustainable hydrogen production, is fundamentally challenged by the relentless chloride ions (Cl^-)-induced corrosion, which impairs catalyst stability during long-term operation. We report a polyhydroquinone (PHQ)-modified electrocatalyst, where the redox-active PHQ layer is firmly coated to CoFe layered double hydroxide (CoFe LDH) surface through a strong hydrogen-bond network. Theoretical calculations and characterization techniques collectively elucidate that the unique interface creates an in situ protective coating, which effectively optimizes the composition of the interfacial water and prevents Cl^- attack. Such a catalyst shows outstanding performance in alkaline seawater, requiring an overpotential of only 335 mV to reach 1 A cm^-2 and exhibiting remarkable durability for 2000 h even at high current densities (j = 1, 1.5, and 2 A cm^-2). Furthermore, the constructed alkaline anion exchange membrane water electrolyzer achieves a j of 1 A cm^-2 at a low voltage of 2.55 V, significantly outperforming the benchmark Pt/C/NF||RuO₂/NF.

Structural regulation of heterogeneous active centers has been widely explored at the nano- and atomic-level, yet achieving subangstrom precision remains highly challenging. Here, we demonstrate subangstrom spatial regulation of the Fe‒N bond within a fully uniform Fe₁-N₄ coordination structure. Strikingly, a 0.1 Å bond compression led to nearly a 23-fold enhancement in C‒H bond oxidation. Advanced characterizations confirmed the uniform low-spin Fe₁-N₄ configuration, with the Fe‒N bond distance gradually decreasing from 2.03 to 1.93 Å during pyrolysis. This subtle structural modification originates from the concerted effect of temperature- and curvature-induced distortion on the curved carbon surface, as further supported by theoretical simulations. The Fe‒N bond distance was found to govern the electronic structure of the Fe center, where compressed coordination promotes electron accumulation. This structural modulation directly results in the high capability for peroxide group activation on Fe₁ single atoms, which affords outstanding C‒H bond oxidation, comparable to supported noble metal catalysts. This study provides the experimental demonstration of structural regulation at subangstrom scale, extending the concept of “precise chemistry” in catalyst design from the nano- and atomic- to the subangstrom scale.

Achieving mild-condition ammonia synthesis from dinitrogen (N₂) reduction has been a longstanding challenge in heterogeneous catalysis, primarily due to the lack of catalysts capable of simultaneously breaking the N≡N bond and hydrogenating the atomic nitrogen with low energy barriers. Herein, we identify a fundamental trade-off between N≡N bond breaking and subsequent N-H bond formation steps across different molecular catalysts, which was not previously established in homogeneous catalysis. By balancing N≡N activation and N-H formation, our computational analysis not only effectively rationalizes experimentally observed activity trends among well-studied Mo-complexes but also offers a rationale for predicting new homogeneous catalysts. Based on this established theoretical structure-activity relationship, we further identified a 5,6-OCF₃-substituted tungsten (W) complex as a promising catalyst for ammonia synthesis, overperforming all available complexes in the literature under the same reaction conditions. This work not only explains the trend in ammonia synthesis activity of metal complexes in available experiments but also provides theoretical guidance for the rational design of next-generation molecular catalysts for ambient nitrogen fixation.

Sulfided NiMo catalysts can effectively hydrogenate oxygen-rich bio-oils into high quality hydrocarbon fuels. However, precisely controlling the cleavage of C−O bonds remains challenging. Here, we synthesized an oil-soluble precursor NiMo₆-DODA by encapsulating the polyoxometalates (POMs) (NH₄)₄[NiMo₆O₂₄H₆] (NiMo₆) with surfactants, followed by in-situ construction of an ultra-dispersed monolayer NiMoS catalyst. The “surfactant shell” of the precursor ensured its homogeneous dispersion in the oil phase, while gradually sacrificing and decomposing during the sulfidation to mitigate the aggregation of the MoS₂ nanosheets. Meanwhile, the well-defined “POMs core” established an atomic-level Ni-Mo proximity, ensuring the dominance of the Ni-promoted MoS₂ active phase. This design not only altered the adsorption configuration of esters on the NiMo catalyst but also introduced abundant edge sulfur vacancies to promote oxygen atom adsorption and accelerate C−O bond cleavage. The results showed that NiMo₆-DODA achieved 100% conversion of methyl palmitate and 100% alkane selectivity under low catalyst loading conditions. Notably, the selectivity for n-hexadecane reached 94.2%, significantly surpassing that obtained with a commercial oil-soluble precursor (69.8%). Furthermore, the catalyst maintained high activity across multiple reaction cycles and in the solvent-free conversion of real bio-oils. This strategy of pre-assembly combined with sacrificial sulfidation provides a simple and effective route for designing hydrodeoxygenation catalysts that enable precise control over ester C−O bond cleavage.

Precise control over product selectivity in heterogeneous catalysis remains a key challenge due to the complex interplay of structural and electronic factors. Here, we demonstrate delicate tuning of product distribution in 1,3-butadiene semi-hydrogenation by engineering the size and composition of Pd-Ag nanostructures. By systematically decoupling size and electronic effects, we identify critical selectivity descriptors and establish structure-selectivity correlations across both monometallic and bimetallic series. The thresholds of ensemble size and Pd valence state for the formation of distinct products are experimentally determined. Integrating kinetic analysis, chemisorption studies, and density functional theory calculations, we show that increased ensemble size and Ag incorporation weaken 1-butene binding and elevate hydrogenation barriers, enabling selective formation of 1-butene (up to 66%) over thermodynamically favored 2-butenes. These insights reveal the fundamental roles of geometric and electronic modulation in governing selectivity and offer a generalizable framework for the rational design of multifunctional bimetallic catalysts.

Methane dry reforming (MDR) converts two major greenhouse gases (CO₂ and CH₄) into syngas (H₂/CO) for synthesizing fuels and chemicals, which provides a process both economically viable and environmentally friendly, aligning with the goal of carbon neutrality. Ni is the most efficient and economic non-noble active metal for MDR but often suffers from deactivation caused by sintering or coking due to the fast C-H activation but sluggish carbon removal. Herein, we report a rather stable Ni catalyst (Ni_BN) derived from electrostatic-driven self-assembled 2D composites, which offered a coke-free manner for a prolonged stability (over 350 h) under typical MDR conditions. This outperformed catalyst featured with homogeneously distributed spherical Ni nanoparticles (~6 nm) stabilized within mixed-oxide matrix. Partially electron-deficient Ni species are tailored by surrounded boron species through the Ni-O-B structure, which hindered the last C-H bond cleavage of methane and accelerated CO₂ reactivity, thus balancing elementary steps to enable a coke-free operation. It marks an important step forward for C-H bond manipulation and inspires material design in other applications.

Nickel-based catalysts are regarded as the most promising candidates for industrial dry reforming of methane (DRM), yet severe coking and metal sintering impede their commercial viability. Herein, we report a CeAlO₃-socketed Ni nanocatalyst with extensive Ni-CeAlO₃ interfaces, demonstrating coke-free stability with no deactivation over 500 h test at 700 °C for a feed of CH₄/CO₂ = 1/1 (undiluted). The socket-structured catalyst was obtained via H₂-reduction-triggered Ni exsolution and simultaneous formation of CeAlO₃ from a Ce₁Al_0.95Ni_0.05O_x composite oxide. A socketed structure featuring extensive Ni-CeAlO₃ interface was achieved upon reduction at 750 °C, which essentially modulated the catalytic activation kinetics of both CO₂ and CH₄. In-situ diffused reflectance infrared Fourier transformed spectroscopy and isotope-labeling experiments were performed to gain insight into the interfacial catalysis, revealing that CO₂ was preferentially activated at the Ni-CeAlO₃ interface to form CO and O*, and CH₄ was subsequently oxidized by O* to form H₂ and another CO through formation of CH₃O* intermediates. Such tandem reaction pathway led to stoichiometric conversion of CO₂ and CH₄ molecules thereby imparting our catalyst to high coking resistance. Our findings shed light on the rational design of a valid Ni-based DRM catalyst with substantial potential for industrial application.

Efficient upgrading of lignin-derived bio-oils requires selective hydrodeoxygenation (HDO) of oxygen-containing groups without hydrogenating the aromatic ring, a central challenge in biomass valorization. Here we combine density functional theory and microkinetic simulations to elucidate the HDO mechanism of guaiacol on copper catalysts. Across Cu(100), Cu(111), and Cu(211) surfaces, two competing routes dominate product distribution: (1) hydrogen-assisted deoxygenation (H-DO) via methoxy dissociation, producing phenol, and (2) partial hydrogenation (PHDO) of the aromatic ring, leading to cyclohexanone-type products. We show that H-DO activity is largely insensitive to surface orientation due to weak Cu-C₂ interactions, whereas PHDO activity depends strongly on surface structure through Cu-C₃/C₆ bonding. This difference establishes the d-band center as a reliable electronic descriptor for selectivity. Cu(111), with its more negative d-band center and weaker adsorption, exhibits the highest aromatic selectivity. Guided by this insight, we propose and validate grain boundary (GB) engineering as a design strategy: Cu(111)/(111) GB selectively suppresses PHDO by destabilizing hydrogenation transition states, while retaining H-DO activity. These results establish a clear structure-activity-selectivity relationship for guaiacol HDO and demonstrate that electronic tuning through facet and GB control provides a general framework for designing metal catalysts for selective biomass upgrading.

Selective hydrogenation of cinnamaldehyde (CAL) to cinnamyl alcohol (COL) using water as the hydrogen source offers a promising route to eliminate traditional H₂ preparation. However, this approach faces a trade-off between concurrently crating abundant active hydroxyls for hydrogenation and readily removing residual oxygen under mild conditions, restricting current development. Here, we report a naturally abundant lattice hydroxyl-mediated selective hydrogenation process over a boehmite-supported gold catalyst (Au/AlOOH), using H₂O as the hydrogen source and CO as the oxygen acceptor. This process achieves 79% CAL conversion and 84% COL selectivity at 90 °C, doubling the efficiency of H₂-based hydrogenation counterpart. In contrast, the OH-free Au/Al₂O₃ shows no activity. Mechanistic studies indicate that the Au/AlOOH boundary provides unsaturated Al³⁺ sites for selective C=O adsorption and lattice hydroxyls for hydrogenation, which are continuously replenished from water. CO adsorbed on Au facilitates oxygen removal, regenerating Al³⁺ sites. This work presents a practical hydrogen transfer strategy that leverages the unique lattice hydroxyls of boehmite to efficiently extract hydrogen from water.

Au nanoclusters (NCs) with atomic-level precision represent an ideal model catalyst enabling efficient CO₂-to-chemical conversion, yet the catalytic performance of distinct active sites in Au NCs remains poorly understood. In this work, ligand-shell engineering has been successfully carried out through a "ligand-stripping pyrolysis" strategy to obtain modified Au₂₅ NCs for electrocatalytic CO₂ reduction reaction (eCO₂RR). Significantly, in situ pyrolysis techniques and structural characterization identify that the exposure of S/Au active sites has been precisely controlled during the adjusted thermal decomposition of the Au NCs, which establishs a clear site-product relationship. The CO/H₂ molar ratio can be precisely adjusted across an exceptionally wide range (0.26-25.47) - a span that encompasses key industrially relevant ratios, such as the 1:2 ratio optimal for Fischer-Tropsch synthesis. Molecular dynamics (MD) simulations quantitatively disclose the interaction trend between exposed S/Au sites and CO₂. S sites exhibit a superior CO₂ affinity, with the local CO₂ concentration increasing as S-site density increases, thereby kinetically promoting eCO₂RR. Theoretical calculations also reveal that S sites facilitate the stabilization of *CO₂ and *CO intermediates and promote electron transfer. In contrast, Au sites are energetically more favorable for the hydrogen evolution reaction. This study establishes an ideal platform for investigating structure-performance relationships of atomically precise NCs and provides guidance for designing metal NCs-based catalysts.