Junction Engineering for Photocatalytic and Photoelectrocatalytic CO₂ Reduction

Abstract

Artificial photosynthesis of clean fuels shows fascinating prospects for solving the energy crisis and environmental pollution. However, the solar conversion efficiency is too low to fulfill industrialization requirements, which is confined by the poor photon utilization, severe recombination of electrons and holes, and insufficient reactive sites. Fortunately, junction engineering displays outstanding performance in conquering the aforementioned problems. Herein, an updated fundamental understanding of various junction engineering for enhancing the efficiency, selectivity, and stability of solar‐driven CO2 reduction is provided. The recent progresses of heterojunctions, homojunctions, and multijunctions for photocatalytic (PC) and photoelectrochemical (PEC) CO2 reduction are focused on, especially their essential roles in facilitating the key PC or PEC processes, including charge separation and transfer, adsorption and activation of CO2, and desorption of products, which may provide an interactively referential development pathway for CO2 photoreduction. Finally, an outlook on the current challenges and perspectives of junction engineering design of photocatalysts for solar‐driven CO2 reduction is provided.

Accelerating Electron‐Transfer and Tuning Product Selectivity Through Surficial Vacancy Engineering on CZTS/CdS for Photoelectrochemical CO2 Reduction

“…[ 4,5 ] Many photocathode materials have been reported to obtain various C1C3 products including CO, [ 6,7 ] HCOOH, [ 8,9 ] methanol, [ 10,11 ] ethanol, [ 12,13 ] and propanol. [ 14 ] However, over the past decades, the stumbling block for PEC CO 2 reduction lies in its low efficiency and uncontrolled product selectivity due to the poor light absorption ability, sluggish charge transfer properties, and high overpotential of commonly used photocathode materials, [ 15,16 ] such as Cu 2 O [ 17 ] and ZnTe. [ 18 ]…”

Plasmonic Active “Hot Spots”‐Confined Photocatalytic CO2 Reduction with High Selectivity for CH4 Production

“…[4,5] Although numerous semiconductor materials have been proven to work for CO 2 photoreduction, the development of semiconductors alone as potential photo catalysts still suffers from their inherent limitations on the light harvesting and utilization. [6][7][8][9][10][11] Thus, it is necessary to exploit new replaceable materials or smart strategies to avoid the drawbacks of semiconductor photocatalysts. Plasmonic nanomaterials are widely considered as fre quencytunable "optical nanoantennas" due to their unique localized surface plasmon resonance (LSPR).…”

Photocatalytic Activity of Supported Metal Nanoparticles and Single Atoms

“…Heterojunctions contain different semiconductor components with matched crystal lattice and dissimilar band energy such as Z‐scheme junction [40] . Morphology and structure of heterojunction influence the photocatalytic performance.…”