Reduced Graphene Oxide as a Solid-State Electron Mediator in Z-Scheme Photocatalytic Water Splitting under Visible Light

Abstract

The effectiveness of reduced graphene oxide as a solid electron mediator for water splitting in the Z-scheme photocatalysis system is demonstrated. We show that a tailor-made, photoreduced graphene oxide can shuttle photogenerated electrons from an O(2)-evolving photocatalyst (BiVO(4)) to a H(2)-evolving photocatalyst (Ru/SrTiO(3):Rh), tripling the consumption of electron-hole pairs in the water splitting reaction under visible-light irradiation.

Z‐Scheme Photocatalytic Systems for Promoting Photocatalytic Performance: Recent Progress and Future Challenges

“…RGO was employed as a solid‐state electron mediator to promote electron transfer between the photocatalyst particles in the Z‐scheme system 27, 48, 59, 60, 61. Kudo et al reported a solid state Z‐scheme system (BiVO 4 )/RGO/(Ru/SrTiO 3 :Rh) for water splitting 61.…”

“…RGO was employed as a solid‐state electron mediator to promote electron transfer between the photocatalyst particles in the Z‐scheme system 27, 48, 59, 60, 61. Kudo et al reported a solid state Z‐scheme system (BiVO 4 )/RGO/(Ru/SrTiO 3 :Rh) for water splitting 61. Under visible light irradiation, the RGO provides pathways for the photogenerated electrons in BiVO 4 and the holes in Ru/SrTiO 3 :Rh to recombine, leaving holes in BiVO 4 and electrons in Ru/SrTiO 3 :Rh to split the water.…”

“…Many works studied different connection modes of Z‐scheme photocatalytic systems 13, 17, 18, 19, 20, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, …”

Constructing CdS/Cd/doped TiO2 Z-scheme type visible light photocatalyst for H2 production

“…Many semiconductors such as, CdS [17,18], AgX [19], g-C 3 N 4 [20], Cu 2 O [21], doped SrTiO 3 [22], CuGaS 2 [23] and others were employed as PSI photocatalyst. Most PSII photocatalysts were chosen from TiO 2 [24], ZnO [25], WO 3 [26], Ag 3 PO 4 [27], BiVO 4 [28], etc. The common electron mediators used were Au [29], Ag [30], Cu [31] and reduced graphene oxide (RGO) [28,32].…”

“…Most PSII photocatalysts were chosen from TiO 2 [24], ZnO [25], WO 3 [26], Ag 3 PO 4 [27], BiVO 4 [28], etc. The common electron mediators used were Au [29], Ag [30], Cu [31] and reduced graphene oxide (RGO) [28,32]. The working principle of Z-scheme is that the light irradiates on both PSI and PSII photocatalysts and then the charge recombination happens between excited electrons from PSII and holes from PSI.…”