Yoon, Joon-Soo Kim, Young-Min Lee, Joo-Won Sung, Yun-Mo 2024-01-19T11:34:30Z 2024-01-19T11:34:30Z 2022-04-29 2022-07 0169-4332 https://pubs.kist.re.kr/handle/201004/114936 Using a wet chemical approach, high-density Ca2Fe2O5 (CFO) nanoflakes were successfully synthesized on a NiO/FTO layer that is an effective hole transport layer (HTL). We found that a two-step annealing strategy could further increase the photoelectrochemical (PEC) efficiency of CFO photocathodes. It was elucidated that two-step annealing was beneficial in various aspects such as morphology, chemical state, optical properties, and impedance. In addition, the NiO HTL further improved the charge transport properties. The CFO on NiO HTL fabricated via two-step annealing demonstrates a photocurrent density of up to-313.7 mu A/cm(2), which is 76 % higher than that of the HTL-free CFO fabricated via single-step annealing. Through DFT calculations, it is revealed that the increase in the concentration of oxygen vacancies at the CFO surface, which was obtained by the two-step annealing process, is beneficial for lowering the relative energy throughout the hydrogen evolution reaction. English Elsevier BV A novel strategy for enhancing photoelectrochemical performance of Ca2Fe2O5 photocathodes: An integrated experimental and DFT-based approach Article 10.1016/j.apsusc.2022.153012 1 APPLIED SURFACE SCIENCE, v.589 APPLIED SURFACE SCIENCE 589 N scie scopus 000780378500002 Chemistry, Physical Materials Science, Coatings & Films Physics, Applied Physics, Condensed Matter Chemistry Materials Science Physics Article HOLE-SELECTIVE LAYER OXYGEN VACANCIES THIN-FILMS WATER CUBI2O4 GROWTH Ca2Fe2O5 photocathodes Photoelectrochemical DFT calculation