电化学形成的PtFeNi合金与含缺陷NiFe LDHs载体之间的电荷转移实现高效水分解

doi:10.1016/S1872-2067(21)63926-8

催化学报 ›› 2022, Vol. 43 ›› Issue (4): 1101-1110.DOI: 10.1016/S1872-2067(21)63926-8

电化学形成的PtFeNi合金与含缺陷NiFe LDHs载体之间的电荷转移实现高效水分解

黄根^a^,^†, 李莹莹^a^,^†, 陈如^a^,^d^,^$(), 肖朝辉^a, 杜石谦^a, 黄裕呈^b^,^c, 谢超^a, 董崇礼^b, 易海波^a^,^#(), 王双印^a^,^*()

^a湖南大学化学化工学院, 化学生物传感与计量学国家重点实验室, 湖南长沙410082
^b淡江大学, X射线科学与物理系研究中心, 台湾新北25137
^c交通大学电物理系, 台湾新竹30010
^d湖南大学深圳研究院, 广州深圳518057

收稿日期:2021-07-21 接受日期:2021-07-21 出版日期:2022-03-05 发布日期:2021-09-06
通讯作者: 陈如,易海波,王双印
作者简介:第一联系人：
^†共同第一作者.
基金资助:
国家重点研发计划(2020YFA0710000);国家自然科学基金(22172047);国家自然科学基金(21902047);国家自然科学基金(21825201);国家自然科学基金(U19A2017);湖南省自然科学基金(2021JJ30089);湖南省自然科学基金(2020JJ5039);湖南省研究生教育创新与专业能力提升项目(CX20200445);低维材料及其应用技术教育部重点实验室(湘潭大学)开放项目(KF20180202);深圳市科技计划项目(JCYJ20210324122209025);长沙市自然科学基金(kq2107008)

Electrochemically formed PtFeNi alloy nanoparticles on defective NiFe LDHs with charge transfer for efficient water splitting

Gen Huang^a^,^†, Yingying Li^a^,^†, Ru Chen^a^,^d^,^$(), Zhaohui Xiao^a, Shiqian Du^a, Yucheng Huang^b^,^c, Chao Xie^a, Chungli Dong^b, Haibo Yi^a^,^#(), Shuangyin Wang^a^,^*()

^aState Key Laboratory of Chem/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, Hunan, China
^bResearch Centre for X-ray Science & Department of Physics, Tamkang University, New Taipei City 25137, Taiwan, China
^cDepartment of Electrophysics, Chiao Tung University, Hsinchu 30010, Taiwan, China
^dShenzhen Research Institute of Hunan University, Shenzhen 518057, Guangdong, China

Received:2021-07-21 Accepted:2021-07-21 Online:2022-03-05 Published:2021-09-06
Contact: Ru Chen, Haibo Yi, Shuangyin Wang
About author:First author contact:
^†Contributed equally to this work.
Supported by:
National Key R&D Program of China(2020YFA0710000);National Natural Science Foundation of China(22172047);National Natural Science Foundation of China(21902047);National Natural Science Foundation of China(21825201);National Natural Science Foundation of China(U19A2017);Natural Science Foundation of Hunan Province(2021JJ30089);Natural Science Foundation of Hunan Province(2020JJ5039);Hunan Graduate Education Innovation Project and Professional Ability Improvement Project(CX20200445);Open Project Program of Key Laboratory of Low Dimensional Materials & Application Technology (Xiangtan University),Ministry of Education, China(KF20180202);Shenzhen Science and Technology Program(JCYJ20210324122209025);Changsha Municipal Natural Science Foundation(kq2107008)

摘要/Abstract

摘要：

氢气是一种能量密度高, 可完全燃烧的清洁能源. 发展绿色制氢技术对于解决全球环境污染, 二氧化碳排放等环境问题具有重要意义. 电化学水分解被认为是一种清洁高效的制氢手段, 可自恰于可再生能源的波动性, 具有效率高、响应快、氢气纯度高等优点. 然而, 由于电化学反应过电位大及动力学缓慢的原因, 驱动电化学水分解的能量消耗巨大. 因此, 开发高效稳定的双功能电解水催化剂对于制氢和减少能源消耗至关重要. 研究表明, 催化剂催化活性中心和载体之间的电荷转移策略是调节催化剂局部电子结构, 提升电催化反应性能的有效手段.
+本文利用简单的电化学循环伏安法在电化学反应池中将微量的Pt锚定到含缺陷的NiFe LDHs载体上. 通过调节循环伏安曲线圈数, 制备了一系列的PtFeNi合金/NiFe LDHs催化剂. 由于NiFe LDHs载体缺陷位点周围的不饱和配位结构, Pt原子容易被缺陷捕获锚定形成成核位点, 同时NiFe LDHs中缺陷位点周围的Fe, Ni原子更容易被电化学还原, 与被缺陷捕获的Pt原子原位结合形成PtFeNi合金纳米粒子, 最终形成PtFeNi合金/NiFe LDHs催化剂. 通过对催化剂结构和表面价态的分析, 构建了相应的模型催化剂. 理论计算结果表明, PtFeNi合金纳米粒子和NiFe LDHs载体之间存在电荷转移再分布现象, 优化了析氢反应(HER)和析氧反应(OER)中间体的吸附, 可以提高HER和OER的电催化活性. 实验结果表明, PtFeNi合金/NiFe LDHs异质结构催化剂分别表现出超高的OER和HER双功能催化活性. 在100 mA cm^-2电流密度下, HER的过电位仅为81 mV, 优于商业化的Pt/C催化剂, 同时OER的过电位仅为243 mV, 优于商业化的IrO₂和大多数LDHs电催化剂, 且该催化剂都能稳定运行24 h. 两电极碱性电解槽测试表明, 只需要1.495和1.578 V电压就可分别达到10和100 mA cm^-2的电流密度, 快速产生氢气和氧气. 因此, PtFeNi合金/NiFe LDHs催化剂在碱性条件电解水制氢方面具有非常好的发展前景. 同时, 本文不但展示了一种独特的缺陷锚定合金纳米粒子, 构建纳米异质结催化剂的方法, 且发现合金纳米粒子和缺陷载体之间存在电荷转移再分布现象, 能够优化电催化反应中间体的吸附, 极大地提升电催化反应性能.

关键词: 析氢反应, 析氧反应, 全解水, 合金异质结构, 层状双金属氢氧化物

Abstract:

Efficient and stable bifunctional electrocatalysts for water splitting is essential for producing hydrogen and alleviating huge energy consumption. Meanwhile, charge transfer engineering is an efficient approach to modulate the localized electronic properties of catalysts and tune the electrocatalytic performance. Herein, we tactfully fabricate PtFeNi alloys/NiFe layered double hydroxides (LDHs) heterostructure by an easily electrochemical way with a small amount of Pt. The experimental and theoretical results unravel that the charge transfer on the alloy clusters modulated by the defective substrates (NiFe LDHs), which synergistically optimizes the adsorption energy of the reaction intermediates. The electrocatalyst exhibits an ultra-low overpotential of 81 and 243 mV at the current density of 100 mA cm^-2for hydrogen evolution and oxygen evolution, respectively. Furthermore, the overall water splitting indicates that PtFeNi alloys/NiFe LDHs presents an ultra-low overpotential of 265 and 406 mV to reach the current density of 10 and 300 mA cm^-2, respectively. It proves that the PtFeNi alloys/NiFe LDHs catalyst is an excellent dual-function electrocatalyst for water splitting and promising for industrialization. This work provides a new electrochemical approach to construct the alloy heterostructure. The prepared heterostructures act as an ideal platform to investigate the charge re-distribution behavior and to improve the electrocatalytic activity.

Key words: Hydrogen evolution reaction, Oxygen evolution reaction, Overall water splitting, Alloy heterostructure, Layered double hydroxides

黄根, 李莹莹, 陈如, 肖朝辉, 杜石谦, 黄裕呈, 谢超, 董崇礼, 易海波, 王双印. 电化学形成的PtFeNi合金与含缺陷NiFe LDHs载体之间的电荷转移实现高效水分解[J]. 催化学报, 2022, 43(4): 1101-1110.

Gen Huang, Yingying Li, Ru Chen, Zhaohui Xiao, Shiqian Du, Yucheng Huang, Chao Xie, Chungli Dong, Haibo Yi, Shuangyin Wang. Electrochemically formed PtFeNi alloy nanoparticles on defective NiFe LDHs with charge transfer for efficient water splitting[J]. Chinese Journal of Catalysis, 2022, 43(4): 1101-1110.

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链接本文: https://www.cjcatal.com/CN/10.1016/S1872-2067(21)63926-8

https://www.cjcatal.com/CN/Y2022/V43/I4/1101

图/表 6

Fig. 1. (a) Schematic representation for the synthesis process of PtFeNi alloys on defective LDHs; SEM image of NiFe LDHs (b) and NiFe LDHs-Ar (c); TEM image of NiFe LDHs (d) and NiFe LDHs-Ar (e); (f) TEM image and the inset HR-TEM image of PtFeNi/NiFe LDHs; (g) EDS mapping image of PtFeNi alloys on NiFe LDHs for PtFeNi/NiFe LDHs-2500.

Fig. 2. (a) Pt 4f XPS spectrum of PtFeNi/NiFe LDHs-2500; (b) Pt L3-edge XANES spectra of PtFeNi/NiFe LDHs-2500, Pt foil and PtO2; (c) the k2-weighted Fourier transform EXAFS spectra of Pt for PtFeNi/NiFe LDHs-2500, Pt foil and PtO2; (d) the Fe 2p XPS spectrum of PtFeNi/NiFe LDHs-2500; (e) Fe K-edge XANES spectra of PtFeNi/NiFe LDHs-2500, Fe foil, α-Fe2O3 and FeO; (f) the k2-weighted Fourier transform EXAFS spectra of PtFeNi/NiFe LDHs-2500, Fe foil, FeO and Alfa-Fe2O3.

Fig. 3. Polarization curves (a) and Tafel plots (b) of the NiFe LDHs-Ar, 20% Pt/C, PtFeNi/NiFe LDHs-2500 and PtFeNi/NiFe LDHs-3500 for the HER; (c) the electrochemical impedance spectroscopy of PtFeNi/NiFe LDHs-2500 and NiFe LDHs-Ar; (d) the initial and after i~t 24 h stability test (the internal illustration) polarization curves of the PtFeNi/NiFe LDHs-2500 for the HER performed at current density of -75 mA cm-2(-0.3 V vs. RHE).

Fig. 4. (a) Polarization curves of NiFe LDHs-Ar, PtFeNi/NiFe LDHs-2500, 20% Pt/C and commercial IrO2 for OER; (b) the cyclic voltammetry of PtFeNi/NiFe LDHs-2500 between 1.23?1.47 V; (c) the electrochemical impedance spectroscopy of NiFe LDHs-Ar and PtFeNi/NiFe LDHs-2500 under OER condition; (d) the initial and after i~t 24 h stability test (the internal illustration) polarization curves of the PtFeNi/NiFe LDHs-2500 for the OER performed at current density of 100 mA cm-2(1.65 V vs. RHE).

Fig. 5. Schematic diagram of overall water splitting (a) and the polarization curves (b) of IrO2 (+) || 20% Pt/C (-) and PtFeNi/NiFe LDHs-2500 (+) & (-) of overall water splitting.

Fig. 6. Optimized structure (a) and schematic diagram (b) of differential charge density of PtFeNi alloy/NiFe LDHs. Iso-surface value is 0.004 e/bohr3. (Yellow and cyan regions represent electron accumulation and depletion, respectively; for the spheres in model, light purple is nickel, brown is iron, gray is platinum, red is oxygen and white is hydrogen); (c) Bader charge analysis of PtFeNi alloy/NiFe LDHs ( The positive values means the atom gets electron) and (d) (PDOS (the Fermi level is set to 0 eV); (e) free energy diagram of HER at Fe, Ni and Pt active sites and (f) OER at different potentials on the active sites of Fe on PtFeNi alloy/NiFe LDHs.

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电化学形成的PtFeNi合金与含缺陷NiFe LDHs载体之间的电荷转移实现高效水分解

Electrochemically formed PtFeNi alloy nanoparticles on defective NiFe LDHs with charge transfer for efficient water splitting

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