Harnessing single phase Cu2ZnSnS4 nanomaterial for photocatalytic degradation of malachite green dye

Abstract

This study explores the cost-effective solvothermal synthesis of Cu₂ZnSnS₄ (CZTS) nanomaterials by optimizing solvothermal temperature parameters. The optical absorption spectrum of CZTS nanomaterials demonstrates absorption within the visible spectrum, with the optical band gap of the synthesised sample series measured in the range (1.46–1.59) eV, indicating its potential suitability for photocatalytic degradation when exposed to visible light irradiation. The crystallinity and phase purity were confirmed through X-Ray Diffraction (XRD), revealing that the crystallite size increases with an increase in solvothermal temperature. Raman spectroscopy was conducted to complement the findings of X-ray diffraction. The purity of the CZTS nanomaterial is evidenced by the absence of any other elemental traces in the EDS pattern. XPS studies indicate the oxidation states and the atomic percentage ratio of Cu:Zn:Sn:S is approximately 2:1:1:4 with significant accuracy.. Cu₂ZnSnS₄ (CZTS), composed of elements that are both abundant and environmentally friendly namely copper, zinc, tin, and sulphur. CZTS presents a promising candidate for applications in environmental remediation, particularly in the degradation of dyes, in addition to its potential in photovoltaic technologies. The photocatalytic activity of CZTS has been examined via the photodegradation of Malachite green dye, resulting in a rate constant (k) of 0.0095 min⁻¹.