Characterizing photocatalysts for water splitting: from atoms to bulk and from slow to ultrafast processes

Abstract

This review provides a comprehensive overview on characterisation techniques for light-driven redox-catalysts highlighting spectroscopic, microscopic, electrochemical and spectroelectrochemical approaches.

Coupling photocatalytic water oxidation with organic reduction: strategy for using water to reduce organic molecules

“…In conclusion, we report, for the first time, that water is used as the electron donor to enable the reductive transformations of organic substances by coupling the light-induced water oxidation half-reaction with the reduction of organic compounds in the presence of Pd/g-C 3 N 4 * photocatalyst, which is different from previous literatures [44][45][46][57][58][59][60][61][62][63][64][65] related to light--driven water splitting where the proton reduction half-reaction is desired to occur, while this half-reaction would inhibit our reactions. The used photocatalyst was synthetized by a novel method where previous Pd/g-C 3 N 4 was irradiated by the light in the presence of Na 2 CO 3 and H 2 O.…”

“…In addition, the reductive coupling of aryl or alkyl halides is of great significance in modern organic synthesis [47][48][49][50][51][52][53][54][55][56] , which has prompted us to select this kind of reaction as the model reaction to make our idea come true. Encouraged by prior success in applying carbon nitride-supported transition metal (M/g-C 3 N 4 ) into photocatalytic water splitting, [57][58][59][60][61][62][63][64][65] we selected this kind of semiconductor to achieve our goals. It is worth noting that the proton reduction is desired in previous literatures related to M/g-C 3 N 4 -catalyzed water splitting, while this half-reaction would inhibit our reaction [44][45][46][57][58][59][60][61][62][63][64][65] .…”

“…Encouraged by prior success in applying carbon nitride-supported transition metal (M/g-C 3 N 4 ) into photocatalytic water splitting, [57][58][59][60][61][62][63][64][65] we selected this kind of semiconductor to achieve our goals. It is worth noting that the proton reduction is desired in previous literatures related to M/g-C 3 N 4 -catalyzed water splitting, while this half-reaction would inhibit our reaction [44][45][46][57][58][59][60][61][62][63][64][65] . Therefore, the M/g-C 3 N 4 and reaction conditions had to be modified to accelerate the water oxidation and inhibit the proton reduction via a new method, and the results are herein reported.…”

Recent Progress in LDH@Graphene and Analogous Heterostructures for Highly Active and Stable Photocatalytic and Photoelectrochemical Water Splitting

“…Therefore, for the sustainable advancement of colonial human being and to make a greener earth for the betterment of the mankind and aquatic life, progress of pollution free and minimum‐energy consumption technologies for clean and renewable energy production as well as environmental recuperative is a vital assignment, which energize researchers to widen new‐fangled techniques to exploit solar energy for a comfort living [5–8] . On this aspect, water splitting process using heterogeneous semiconductor photocatalyst mimicking the natural photosynthesis received considerable attention as a green and sustainable technology owing to its pivotal prospective to solve energy crises and environmental issues [5–30] . Semiconductor photocatalysts for water splitting exhibits superior advantages as compared to conventional catalyst involving multiple steps, higher reaction parameter.…”

Microelectrode-based transient amperometry of O2adsorption and desorption on a SrTiO3photocatalyst excited under water

“…Oxygen evolution at water-solid interfaces is a key reaction for sustainable energy production. [1][2][3][4] In semiconductor photocatalysts and photoelectrodes, the creation and consumption kinetics of bandgap-excited charge carriers [5][6][7][8][9][10][11][12][13][14] or chemical intermediates [15][16][17][18][19][20] have been traced using transient absorption spectroscopy (TAS) with good time resolutions of femtoseconds to milliseconds. The kinetics observed by TAS for the initial and intermediate species must be compared with O 2 evolution kinetics to verify or deny a proposed reaction mechanism.…”