Synthesis of hexagonal rosettes of g-C3N4 with boosted charge transfer for the enhanced visible-light photocatalytic hydrogen evolution and hydrogen peroxide production

Abstract

Photocatalytic sustainable fuel production attracted extensive attention because of the urgent need of the society to shift from fossil fuels to solar fuels. Herein, the synthesis of hexagonal rosettes of g-C3N4 with an efficient performance toward hydrogen evolution and hydrogen peroxide production as the two kinds of solar fuels were reported. The hexagonal rosettes of g-C3N4 were simply fabricated via controlled solid-state polymerization of three-dimensional hexagonal rosettes of cyanuric acid-melamine adduct at 500 degrees C. The hexagonal rosettes of g-C3N4 showed an amorphous nature with an extremely high surface area of 400 m(2) g(-1). Also, the as-obtained catalyst demonstrated remarkable photocatalytic activity in hydrogen production of 1285 mu mol g(-1) h(-1) and hydrogen peroxide production of 150 lmol g(-1) h(-1). The mechanism for the polymerization process of the cyanuric acid-melamine (CM) complex to hexagonal rosettes of g-C3N4 was thoroughly described employing electron microscopy tools. This study identified that the CM complex condensation is accomplished via a dehydration process by producing a highly condensed and active structure of g-C3N4, which is different from the previously reported condensation mechanism of the melamine and its derivatives performed through a deamination process. (C) 2021 Elsevier Inc. All rights reserved.