Environmentally sustainable biogenic fabrication of AuNP decorated-graphitic g-C3N4 nanostructures towards improved photoelectrochemical performances

Abstract

<div>Noble-metal gold (Au) nanoparticles (NPs) anchored/decorated on polymeric graphitic carbon nitride (g-</div><div>C3N4), as a nanostructure, was fabricated by a simple, single step, and an environmentally friendly</div><div>synthesis approach using single-strain-developed biofilm as a reducing tool. The well deposited/</div><div>anchored AuNPs on the sheet-like structure of g-C3N4 exhibited high photoelectrochemical</div><div>performance under visible-light irradiation. The Au-g-C3N4 nanostructures behaved as a plasmonic</div><div>material. The nanostructures were analyzed using standard characterization techniques. The effect of</div><div>AuNPs deposition on the photoelectrochemical performance of the Au-g-C3N4 nanostructures was</div><div>examined by linear sweep voltammetry (LSV), electrochemical impedance spectroscopy (EIS), incident</div><div>photon-to-current efficiency (IPCE) and cyclic voltammetry (CV) in the dark and under visible-light</div><div>irradiation. The optimal charge transfer resistance for Au-g-C3N4 nanostructures (6 mM) recorded at</div><div>18.21 1.00 U cm2 and high electron transfer efficiency, as determined by EIS. The improved</div><div>photoelectrochemical performance of the Au-g-C3N4 nanostructures was attributed to the synergistic</div><div>effects between the conduction band minimum of g-C3N4 and the plasmonic band of AuNPs, including</div><div>high optical absorption, uniform distribution, and nanoscale particle size. This simple, biogenic approach</div><div>opens up new ways of producing photoactive Au-g-C3N4 nanostructures for potential practical</div><div>applications, such as visible light-induced photonic materials for real device development.</div