Decoration of Carbon Nitride Surface with Bimetallic Nanoparticles (Ag/Pt, Ag/Pd, and Ag/Au) via Galvanic Exchange for Hydrogen Evolution Reaction

5 years ago

Decoration of Carbon Nitride Surface with Bimetallic Nanoparticles (Ag/Pt, Ag/Pd, and Ag/Au) via Galvanic Exchange for Hydrogen Evolution Reaction

Mrinmoyee Basu, Pragati Fageria, Roshan Nazir, Surojit Pande

Here, we propose the synthesis of AgPt, AgPd, and AgAu bimetallic nanoparticles (NPs) on a carbon nitride (C₃N₄) surface via a galvanic exchange technique for the hydrogen evolution reaction (HER). Prior to the synthesis of C₃N₄/AgPt, AgPd, and AgAu, Ag NPs were synthesized on a C₃N₄ surface. For the synthesis of Ag NPs, initially Ag⁺ ions were adsorbed and then reduced by NaBH₄ resulting in the decoration of Ag NPs. These Ag NPs were then subjected to galvanic exchange where sacrificial Ag was replaced by Pt²⁺, Pd²⁺, and Au³⁺ to fabricate AgPt, AgPd, and AgAu NPs. The galvanic exchange reaction occurs on a solid substrate, which favored slow exchange of Ag and resulted in the transformation of Ag into AgPt, AgPd, and AgAu alloys. The synthesized heterostructures were characterized with the help of PXRD, XPS, TEM, FESEM, and EDS techniques. All the materials were applied for hydrogen evolution using 0.5 M H₂SO₄ solution. C₃N₄/AgPt shows efficient electrocatalytic activity as it requires only −150 mV potential to attain current density of 10 mA/cm². Bimetallic catalysts synthesized through galvanic exchange proved very efficient as compared to monometallic C₃N₄/Ag.

Publisher URL: http://dx.doi.org/10.1021/acs.jpcc.7b04595

DOI: 10.1021/acs.jpcc.7b04595