One-Step Synthesis of Visible Range Luminescent Multicomponent Semiconductor Composites Based on Graphitic Carbon Nitride

Abstract

Using ternary g-C3N4/ZnO/ZnS bulk composites as an example, it is demonstrated that g-C3N4-based heterojunction systems can be synthesized in a onestep process by pyrolytic decomposition of a mechanical mixture of only two chemical precursors, i.e., thiourea and zinc acetate dehydrate, at 500–625 °C with subsequent in situ interaction and polymerization of the products. Scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) analyses reveal that the synthesized composites consist of intermixed alloyed g-C3N4, ZnO, and ZnS grains with good crystalline quality. The materials demonstrate bright photoluminescence (PL) at room temperature in the photon energy range of 1.5–3.0 eV (410–800 nm) which can be tuned by the synthesis temperature. A phase sequence during the synthesis and peculiarities of the PL are discussed.