Highly Efficient Visible Light Photocatalytic Reduction of CO₂ to Hydrocarbon Fuels by Cu-Nanoparticle Decorated Graphene Oxide

Abstract

The production of renewable solar fuel through CO2 photoreduction, namely artificial photosynthesis, has gained tremendous attention in recent times due to the limited availability of fossil-fuel resources and global climate change caused by rising anthropogenic CO2 in the atmosphere. In this study, graphene oxide (GO) decorated with copper nanoparticles (Cu-NPs), hereafter referred to as Cu/GO, has been used to enhance photocatalytic CO2 reduction under visible-light. A rapid one-pot microwave process was used to prepare the Cu/GO hybrids with various Cu contents. The attributes of metallic copper nanoparticles (∼4-5 nm in size) in the GO hybrid are shown to significantly enhance the photocatalytic activity of GO, primarily through the suppression of electron-hole pair recombination, further reduction of GO's bandgap, and modification of its work function. X-ray photoemission spectroscopy studies indicate a charge transfer from GO to Cu. A strong interaction is observed between the metal content of the Cu/GO hybrids and the rates of formation and selectivity of the products. A factor of greater than 60 times enhancement in CO2 to fuel catalytic efficiency has been demonstrated using Cu/GO-2 (10 wt % Cu) compared with that using pristine GO.

SnSx (x = 1, 2) Nanocrystals as Effective Catalysts for Photoelectrochemical Water Splitting

“…Due to quantum confinement effects of 2-D SnS nanosheets, the SnS thin films display the strong blue shift (~0.2 eV) as compared to previously published reports (~1.2eV) [46]. The positions of the conduction bands (E CB ) for SnS and SnS 2 were calculated based on the onset potentials for the reduction reactions of these materials [47]. The conduction band positions for the SnS and SnS 2 thin-film electrocatalysts are −0.65 and −0.55 V vs. Ag/AgCl, respectively (Supplementary Materials Figure S6a,b).…”

Microwave, Ultrasound, and Mechanochemistry: Unconventional Tools that Are Used to Obtain “Smart” Catalysts for CO2 Hydrogenation

“…The positive photocatalytic performance towards CO2 reduction to CH3OH observed when Cu NPs were present ( Figure 7) was ascribed to a synergistic mechanism of Cu NPs at the surface of TiO2 (Scheme 3): Cu NPs obtained by MW-assisted reduction method likely suppressed the recombination of charge carriers and improved the charge transfer efficiency. In another study, Cu-Graphene Oxide (Cu/GO) composite photocatalysts were obtained using a simple and rapid one-pot MW process [55], shown in Figure 8a. The positive photocatalytic performance towards CO 2 reduction to CH 3 OH observed when Cu NPs were present ( Figure 7) was ascribed to a synergistic mechanism of Cu NPs at the surface of TiO 2 (Scheme 3): Cu NPs obtained by MW-assisted reduction method likely suppressed the recombination of charge carriers and improved the charge transfer efficiency.…”

“…The positive photocatalytic performance towards CO2 reduction to CH3OH observed when Cu NPs were present ( Figure 7) was ascribed to a synergistic mechanism of Cu NPs at the surface of TiO2 (Scheme 3): Cu NPs obtained by MW-assisted reduction method likely suppressed the recombination of charge carriers and improved the charge transfer efficiency. In another study, Cu-Graphene Oxide (Cu/GO) composite photocatalysts were obtained using a simple and rapid one-pot MW process [55], shown in Figure 8a. In another study, Cu-Graphene Oxide (Cu/GO) composite photocatalysts were obtained using a simple and rapid one-pot MW process [55], shown in Figure 8a.…”

“…In another study, Cu-Graphene Oxide (Cu/GO) composite photocatalysts were obtained using a simple and rapid one-pot MW process [55], shown in Figure 8a. In another study, Cu-Graphene Oxide (Cu/GO) composite photocatalysts were obtained using a simple and rapid one-pot MW process [55], shown in Figure 8a. By using Cu(NO3)2 as metal precursor, short MW heating (ca.…”

Introduction

“…AA, AB and ABC, was found in chemical vapour deposition (CVD)-grown samples [28][29][30][31][32][33][34][35][36][37][38][39][40]. The improved quality is adequate for research experiments and industrial applications [41][42][43][44][45][46][47][48][49]. In addition, AAB stacking and intermediate bilayer configurations, with relative layer-layer shifts or twists, have also been found and are becoming interesting subjects [59][60][61][62][63][64][65][66][67].…”