Boosting photocarrier collection in semiconductors by synergizing photothermoelectric and photoelectric. (March 2023)

• Record Type: Journal Article
• Authors: Tan, Bing; Sun, Mengdi; Liu, Bo; Jiang, Xiao; Feng, Qingliang; Xie, Erqing; Xi, Pinxian; Zhang, Zemin
• Is Part Of: Nano energy. Volume 107(2023)
• Publication Date: 2023-03
• Subjects: Charge collection -- Diffusion length -- Photothermotronic -- Internal electric field -- H2O2 production; Nanoscience -- Periodicals; Nanotechnology -- Periodicals; Nanostructured materials -- Periodicals; Power resources -- Technological innovations -- Periodicals; Nanoscience; Nanostructured materials; Nanotechnology; Power resources -- Technological innovations; Periodicals; 621.042
• DOI: 10.1016/j.nanoen.2022.108138
• Languages: English
• ISSNs: 2211-2855

Abstract

Abstract: Efficient generation and collection of photocarriers is a contradiction for most metal oxide semiconductors. An approach to better understanding and controlling photocarriers' special collection is critical for solar-fuel conversation. Herein, p-type BiFeO3 was chosen to reveal the diffusion length (∼34 nm) limited performance and to develop an approach to boosting photocarrier collection by synergizing photothermoelectric and photoelectric. In this approach, efficient photocarrier collection was realized by two processes: 1) an inner photothermoelectric voltage as the carriers' driving force to promote drift in the flat band region; 2) the accumulated electrons in the cooling interface consumed photogenerated holes and inhibited recombination. As a result, the composite photocathode shows a state-of-the-art photocurrent of − 0.49 mA·cm −2 and an H2 O2 generation rate of 695 mmol/(L·m 2 ). This work aims to provide a broader understanding of photocarrier collection's limited performance of metal oxide photoelectrode and explore a universal approach to improving it without extra power input. Graphical Abstract: High-efficient photosynthetic H2 O2 production is realized on BiFeO3 -based composite photocathode benefiting from optical computations and synergy of photothermoelectric and photoelectric. ga1 Highlights: Optical calculations reveal the diffusion length limited charge collection of BiFeO3 . Photothermotronic can construct an inner electric field within semiconductor films. Electric field as driving force to boost charge collection in the flat band region. The composite photocathode achieved an H2 O2 production of 695 mmol/(L·m 2 ).