Microwave-induced growth of {1010} faceted zinc oxide/graphene 2D/2D nanostructures for visible-light photocatalysis and hydrogen evolution reaction

The future hydrogen economy urges to replace platinum-based catalysts since large-scale production of hydrogen using platinum is not economically viable to deal with the influx of interest. Developing cost-effective, durable, and efficient catalysts is one of the most relevant research frontiers. Herein, inter-connected and {1010} faceted 2D zinc oxide decorated on graphene sheets was effectively fabricated by a simple CTAB-assisted microwave technique and has been intensively investigated for photocatalytic dye degradation and electrocatalytic hydrogen evolution. The XRD and Raman spectra confirm the in-situ re-duction of GO to rGO and successful synthesis of ZnO/rGO hybrids. Compared with the pure ZnO, as -ob-tained ZnO/rGO hybrids exhibited good stability and superior photocatalytic efficiency under visible-light irradiation, owing to reduced electron-hole pair recombination upon GO incorporation, as affirmed by PL spectra, TRPL lifetime measurements, and photocurrent responses. The 2D/2D ZnO/rGO hybrid nanos-tructure showed optimised material properties for exceptional electrochemical H2 evolution, producing a current density of - 10 mA/cm2 at a significantly reduced overpotential of - 810 mV vs. RHE, and a Tafel slope of 157 mV/dec in 0.5 M H2SO4. The enhanced catalytic activity can be attributed to the introduction of rGO sheets, which improved the surface area and electrical conductivity of the sample. The multifunctional nature of ZnO/rGO hybrids in both photocatalysis and electrocatalysis sheds light upon environmental pollution and the energy crisis.(c) 2023 Elsevier B.V. All rights reserved.

Automated summary

In the future hydrogen economy, there is a need to replace platinum-based catalysts due to economic constraints. Developing cost-effective, durable, and efficient catalysts is a relevant research frontier.