Cocatalysts for Selective Photoreduction of CO₂into Solar Fuels

Abstract

Photoreduction of CO2 into sustainable and green solar fuels is generally believed to be an appealing solution to simultaneously overcome both environmental problems and energy crisis. The low selectivity of challenging multi-electron CO2 photoreduction reactions makes it one of the holy grails in heterogeneous photocatalysis. This Review highlights the important roles of cocatalysts in selective photocatalytic CO2 reduction into solar fuels using semiconductor catalysts. A special emphasis in this review is placed on the key role, design considerations and modification strategies of cocatalysts for CO2 photoreduction. Various cocatalysts, such as the biomimetic, metal-based, metal-free, and multifunctional ones, and their selectivity for CO2 photoreduction are summarized and discussed, along with the recent advances in this area. This Review provides useful information for the design of highly selective cocatalysts for photo­(electro)­reduction and electroreduction of CO2 and complements the existing reviews on various semiconductor photocatalysts.

Ordered colloidal clusters constructed by nanocrystals with valence for efficient CO 2 photoreduction

“…Under visible light irradiation, the Ru(bpy) 3 2+ photosensitizer is motivated to the excited state Ru(bpy) 3 2+ *, which will be reductively quenched by the electron donor TEOA to form the reduced state Ru(bpy) 3 + . Afterward, the excited electrons of the reduced photosensitizer would delocalize and transfer to the porous CCs that act as cocatalysts (51), and then reduce the adsorbed CO 2 molecules to form CO. During this process, the electron donor TEOA is oxidized to aldehydes ( fig. S36) (63), thus accomplishing the redox cycle of the CO 2 photoreduction catalysis.…”

Graphdiyne: A New Photocatalytic CO2 Reduction Cocatalyst

“…Herein, a novel GDY cocatalyst coupled TiO 2 nanofibers for boosted photocatalytic CO 2 reduction, synthesized by an electrostatic selfassembly approach is reported. [21,22] Up to now, various cocatalysts have been exploited to promote the photocatalytic performance of TiO 2 and the most widely used cocatalysts were noble metals, such as Pt, Pd, Au, Ag, and their alloys. The theoretical simulation further implies strong chemisorption and deformation of CO 2 molecules upon GDY, which can be verified by in situ diffuse reflectance infrared Fourier transform spectroscopy.…”

“…[6][7][8][9][10][11] As one of the most popular photocatalytic materials, TiO 2 is chemically stable, nontoxic and earth-abundant to be proverbially utilized for CO 2 photoreduction. [21,22] Up to now, various cocatalysts have been exploited to promote the photocatalytic performance of TiO 2 and the most widely used cocatalysts were noble metals, such as Pt, Pd, Au, Ag, and their alloys. [17][18][19][20] Modifying TiO 2 with a cocatalyst has been widely adopted to tackle this issue owing to the advantages of cocatalysts such as improving the selectivity, minimizing the overpotentials, promoting the charge separation, enhancing the adsorption of CO 2 , suppressing the photocorrosion and so on.…”

Defect Engineering of Photocatalysts for Solar Energy Conversion

“…With increasing energy demands, environmental concerns, and even climate change issues, exploiting renewable energy sources and developing low‐cost energy utilization routes are of great significance for our modern society . Among various renewable energy sources, solar energy is regarded as promising one meeting the imperative societal demand for sustainable clean energy due to its inexhaustibility, universality, high capacity, and environmental friendliness.…”