Wang Ziyu, Qin Yimo, Wu Xin, He Kui, Li Xiaolong, Wang Juan
Shanghai Key Laboratory of Materials Protection and Advanced Materials in Electric Power, Shanghai University of Electric Power, Shanghai 200090, People's Republic of China.
Guangdong Provincial Key Laboratory of Distributed Energy Systems, Dongguan University of Technology, Dongguan 523419, People's Republic of China.
Nanotechnology. 2022 Sep 20;33(49). doi: 10.1088/1361-6528/ac8a51.
Solar-driven photoelectrochemical (PEC) water splitting for hydrogen generation is regarded as a sustainable strategy to relieve fossil resource issue. However, its PEC conversion efficiency still suffers from the low light absorption and high electron-hole recombination. Herein, we report 1D/2D hierarchical heterostructured photoelectrode constructed by ordered ZnO nanorod array and intimately attached ultra-thin Hematene (thickness of monolayer: 1-2 nm) for effective PEC water oxidation with visible light irradiation. The onset potential of Hematene/ZnO NRs photoanode (0.28 V versus RHE) for PEC water oxidation has an obvious negative shift compared with that of ZnO NRs (0.32 V versus RHE) indicating the enhanced PEC kinetics. Furthermore, reduced charge transport resistance (18.82 KΩ cm), a high carrier density of 9.03 × 10cmand the resulting significantly enhanced incident photon-to-current efficiency enhancement compared with ZnO NRs photoanode were obtained for Hematene/ZnO NRs photoanode. All these were ascribed to the formation of large built-in electric field which was arising from the charge redistribution at the ZnO and Hematene interface, and the band alignment engineering between the components. In summary, such interfacial engineering may inspire the future development of 1D/2D hierarchical heterostructured photoanodes in the field of PEC water splitting.
太阳能驱动的光电化学（PEC）水分解制氢被视为缓解化石资源问题的可持续策略。然而，其PEC转换效率仍受限于低光吸收和高电子-空穴复合率。在此，我们报道了一种由有序的ZnO纳米棒阵列和紧密附着的超薄血红素（单层厚度：1-2纳米）构建的一维/二维分级异质结构光电极，用于在可见光照射下进行高效的PEC水氧化。与ZnO纳米棒（相对于可逆氢电极，起始电位为0.32 V）相比，血红素/ZnO纳米棒光阳极用于PEC水氧化的起始电位（相对于可逆氢电极，为0.28 V）有明显的负向偏移，这表明PEC动力学得到了增强。此外，与ZnO纳米棒光阳极相比，血红素/ZnO纳米棒光阳极的电荷传输电阻降低（18.82 KΩ cm），载流子密度高达9.03×10cm，入射光子-电流效率显著提高。所有这些都归因于在ZnO和血红素界面处电荷重新分布以及各组分之间的能带排列工程所产生的大的内建电场的形成。总之，这种界面工程可能会激发一维/二维分级异质结构光阳极在PEC水分解领域的未来发展。
