Controllable interface engineering of g-C3N4/CuS nanocomposite photocatalysts

The rational fabrication of an efficient photocatalyst with optimal interface engineering remains a huge challenge for the enhancement of photocatalytic perpformance. Herein, a sequence of multidimensional nanocomposites with different spatial interfaces, including point, and line or face-contact surface are controllable designed by horizontal growing diverse dimensional (0D, 1D,2D and 3D) copper sulfide (CuS) on 2D graphitic-carbon nitride (g-C3N4) nanosheets. Physical and photochemical measurements demonstrate that the formation of an extraordinary 2D/2D face-to-face contact interface can not only enhance the specific surface area, visible light utilization, and photo-excited charge separation efficiency, but also elevate the density and lifetime of photo-generated carriers. The results of ultraviolet photoemission spectroscopy (UPS) and density functional theory (DFT) calculation also confirm that charge transfer tends to occur in face-to-face contact. Among the types of nanocomposites considered, 2D/2D g-C3N4/CuS has the smallest electron transfer barrier (CYRILLIC CAPITAL LETTER EFBe) between active species, thereby displaying the maximum photo catalytic apparent rate constant, which is about 12 times larger than that of pristine g-C3N4. Most importantly, this work systematically investigates the relationship between microscopic interface structure and photocatalytic activity from the perspective of the optical, and electrical and energy levels, providing a new insight on the rational design of desired interface engineering towards efficient photocatalysts. (c) 2022 Elsevier B.V. All rights reserved.