Departament de Química Física i Institut Universitari d'Electroquímica, Universitat d'Alacant, Apartat 99, E-, 03080, Alicante, Spain.
ChemSusChem. 2017 Jun 9;10(11):2457-2463. doi: 10.1002/cssc.201700166. Epub 2017 May 8.
The development of tandem devices for water photosplitting requires the preparation of photocathodic materials based on earth-abundant elements that show long-term stability in aqueous electrolytes. Ternary metal oxides seem to be a viable option, among which perovskites stand out. In this context, transparent and compact LaFeO thin-film electrodes have been prepared by a sol-gel process, both undoped and doped with metals (M) such as Mg or Zn. Pristine electrodes support the development of cathodic photocurrents in 0.1 m NaOH aqueous solutions, particularly in the presence of oxygen, with an onset potential as high as 1.4 V versus the reversible hydrogen electrode. Doping with Mg or Zn leads to an important enhancement of the photocurrent, which peaks for a stoichiometry of LaFe M O with a sixfold enhancement with respect to the pristine material. Such an improvement is attributed to an increase in both the density and mobility of the majority carriers, although a contribution of surface passivation cannot be excluded.
串联器件的发展用于水光解需要制备基于丰富元素的光阴极材料，这些材料在水电解液中具有长期稳定性。三元金属氧化物似乎是一种可行的选择，其中钙钛矿尤为突出。在此背景下，通过溶胶-凝胶工艺制备了透明且致密的 LaFeO 薄膜电极，包括未掺杂和掺杂金属（如 Mg 或 Zn）的电极。原始电极在 0.1 m NaOH 水溶液中支持阴极光电流的发展，特别是在存在氧气的情况下，起始电位高达相对于可逆氢电极 1.4 V。掺杂 Mg 或 Zn 会导致光电流显著增强，对于具有六倍增强相对于原始材料的化学计量比的 LaFeMO，光电流达到峰值。这种改善归因于多数载流子的密度和迁移率的增加，尽管不能排除表面钝化的贡献。
