Zhang Wenmin, Wang Shanshan, Yang Shengyuan A, Xia Xing-Hua, Zhou Yi-Ge
Institute of Chemical Biology and Nanomedicine (ICBN), State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, P. R. China.
Research Laboratory for Quantum Materials, Singapore University of Technology and Design, Singapore, 487372, Singapore and School of Physics, Southeast University, Nanjing, 211189, China.
Nanoscale. 2020 Aug 28;12(33):17290-17297. doi: 10.1039/d0nr04562d.
Electrocatalytic water splitting holds great promise for renewable energy conversion and storage systems. However, it usually suffers from sluggish kinetics, which greatly hinders its real application. Here, we demonstrate the utilization of the localized surface plasmon resonance (LSPR) of Au nanorods (AuNRs) to significantly improve the electroactivity of both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) at Co-MOF nanosheets (Co-MOFNs) under different polarizations. Theoretical calculations suggest that the HER enhancement can be largely attributed to the injection of hot electrons from plasmonic AuNRs to Co-MOFN catalysts, which upraises the Fermi level of Co-MOFNs, increasing their reductive activity towards the HER. Regarding the promotion of the OER, it is indicated that the formed holes in Co-MOFNs should majorly locate on the surface oxygen atoms, which may also serve as active positions working jointly with neighboring Co atoms in oxidizing OH-. The plasmon enhanced HER and OER electrocatalysis could also be observed over AuNR/Ni-MOFN and AuNR/NiCo-MOFN catalysts, suggesting the generality of this strategy. This study highlights the possibility of accelerating both the HER and OER efficiency by AuNR plasmonic excitation and provides a new route towards the design of more efficient water splitting systems with the assistance of light energy.
电催化水分解对于可再生能源转换和存储系统具有巨大的潜力。然而，它通常存在动力学迟缓的问题，这极大地阻碍了其实际应用。在此，我们展示了利用金纳米棒（AuNRs）的局域表面等离子体共振（LSPR），在不同极化条件下显著提高钴基金属有机框架纳米片（Co-MOFNs）上析氢反应（HER）和析氧反应（OER）的电活性。理论计算表明，HER活性的增强主要归因于等离子体AuNRs向Co-MOFN催化剂注入热电子，这提高了Co-MOFNs的费米能级，增强了它们对HER的还原活性。关于OER的促进作用，研究表明Co-MOFNs中形成的空穴主要位于表面氧原子上，这些氧原子也可能作为与相邻钴原子共同作用氧化OH-的活性位点。在AuNR/Ni-MOFN和AuNR/NiCo-MOFN催化剂上也观察到了等离子体增强的HER和OER电催化作用，表明该策略具有通用性。这项研究突出了通过AuNR等离子体激发提高HER和OER效率的可能性，并为借助光能设计更高效的水分解系统提供了一条新途径。
