Unravelling the Photocatalytic Behavior of All-Inorganic Mixed Halide Perovskites: The Role of Surface Chemical States

6533b871fe1ef96bd12d0f2f

RESEARCH PRODUCT

Unravelling the Photocatalytic Behavior of All-Inorganic Mixed Halide Perovskites: The Role of Surface Chemical States

Seog Joon Yoon Seog Joon Yoon Sofia Masi Rogelio Ospina Eliseo Amado-gonzález Andrés F. Gualdrón-reyes Andrés F. Gualdrón-reyes Jhonatan Rodriguez-pereira Juan M. Tirado Sixto Gimenez Said Agouram Franklin Jaramillo Vicente Muñoz-sanjose Jorge Rueda-p Iván Mora-seró

subject

photocatalytic activity Materials science Iodide Halide 02 engineering and technology 010402 general chemistry 01 natural sciences 7. Clean energy iodide vacancies Surface chemical General Materials Science hot-injection Perovskite (structure)chemistry.chemical_classification anion-exchange degradation pathways Ion exchange surface chemical states 021001 nanoscience & nanotechnology 0104 chemical sciences Nanocrystal Chemical engineering chemistry Photocatalysis Degradation (geology)0210 nano-technology superoxide ions

description

Within the most mesmerizing materials in the world of optoelectronics, mixed halide perovskites (MHPs) have been distinguished because of the tunability of their optoelectronic properties, balancing both the light-harvesting efficiency and the charge extraction into highly efficient solar devices. This feature has drawn the attention of analogous hot topics as photocatalysis for carrying out more efficiently the degradation of organic compounds. However, the photo-oxidation ability of perovskite depends not only on its excellent light-harvesting properties but also on the surface chemical environment provided during its synthesis. Accordingly, we studied the role of surface chemical states of MHP-based nanocrystals (NCs) synthesized by hot-injection (H-I) and anion-exchange (A-E) approaches on their photocatalytic (PC) activity for the oxidation of β-naphthol as a model system. We concluded that iodide vacancies are the main surface chemical states that facilitate the formation of superoxide ions, O2●–, which are responsible for the PC activity in A-E-MHP. Conversely, the PC performance of H-I-MHP is related to the appropriate balance between band gap and a highly oxidizing valence band. This work offers new insights on the surface properties of MHP related to their catalytic activity in photochemical applications.

year	journal	country	edition	language
2019-01-01

10.1021/acsami.9b19374 https://doi.org/10.1021/acsami.9b19374