A novel graphdiyne (C _n H _{2 n−2} ) preparation strategy: calcium carbide-derived graphdiyne film supported cobalt tetroxide nanoneedles for photocatalytic hydrogen production

Abstract

Guiding the directional and effective migration of photocarriers is a basic strategy to achieve high performance of catalysts in the photocatalytic water splitting process.

Abstract

Guiding the directional and effective migration of photocarriers is a basic strategy to achieve high performance of catalysts in the photocatalytic water splitting process. In this paper, a new carbon material of graphdiyne (GDY) was prepared by a mechanical ball milling method, and then it was introduced into metal oxide Co ₃O ₄ by an ultrasonic in situ stirring method. The lamellar film structure of GDY provides effective support for Co ₃O ₄ nanoneedles. It is undeniable that the Co ₃O ₄/GDY composite has excellent photocatalytic performance for hydrogen production. The highest hydrogen production activity of Co ₃O ₄/GDY-20 is 2456 μmol g ⁻¹, which is 7.7 times that of pure Co ₃O ₄. In addition, the successful construction of the two-phase S-scheme heterojunction creates favorable conditions for photoelectron migration, and separates the photoelectron–hole pairs successfully. Ultraviolet diffuse reflectance spectra reflect the light absorption capacity of the composite in a wide light wavelength range. Fluorescence spectra and electrochemical detection confirm that photoelectron migration in the composite is effectively regulated, which is very conducive to photocatalytic water splitting. The study shows that the introduction of carbon materials into metal oxides has great potential in the field of photocatalysis.