Bandgap funneling in bismuth-based hybrid Perovskite photocatalyst with efficient visible-light-driven hydrogen evolution

Yunqi Tang, Chun Hong Mak, Chen Wang, Yu Fu, Fang-Fang Li, Guohua Jia, Chang-Wei Hsieh, Hsin-Hui Shen, Juan Carlos Colmenares, Haisheng Song, Mingjian Yuan, Yue Chen, Hsien-Yi Hsu

Research output: Contribution to journalArticleResearchpeer-review

15 Citations (Scopus)


The photocatalytic system using hydrohalic acid (HX) for hydrogen production is a promising strategy to generate clean and renewable fuels as well as value-added chemicals (such as X2/X3). However, it is still challenging to develop a visible-light active and strong-acid resistive photocatalyst. Hybrid perovskites have been recognized as a potential photocatalyst for photovoltaic HX splitting. Herein, a novel environmentally friendly mixed halide perovskite MA3Bi2Cl9–xIx with a bandgap funnel structure is developed, i.e., confirmed by energy dispersive X-ray analysis and density functional theory calculations. Due to gradient neutral formation energy within iodine-doped MA3Bi2Cl9, the concentration of iodide element decreases from the surface to the interior across the MA3Bi2Cl9–xIx perovskite. Because of the aligned energy levels of iodide/chloride-mixed MA3Bi2Cl9–xIx, a graded bandgap funnel structure is therefore formed, leading to the promotion of photoinduced charge transfer from the interior to the surface for efficient photocatalytic redox reaction. As a result, the hydrogen generation rate of the optimized MA3Bi2Cl9–xIx is enhanced up to ≈341 ± 61.7 µmol h−1 with a Pt co-catalyst under visible light irradiation.

Original languageEnglish
Article number2200326
Number of pages9
JournalSmall Methods
Issue number8
Publication statusPublished - 18 Aug 2022


  • bandgap funneling
  • hydrogen evolution
  • lead-free hybrid perovskites
  • photocatalysis

Cite this