Microwave-Assisted Synthesis of MnSeTe Nanocomposite Flowers for Optoelectronic and Photoresponse Applications

Abstract

The tuning of optical, morphological, and structural properties through precise control of the size/thickness of transition-metal chalcogenide is one of the key aspects for practical applications. The present study reports that the microwave-synthesized MnSe_1+xTe_1–x (MST) nanocomposite by altering Se and Te concentrations is studied for optoelectronic applications. The gradual increase in its crystallinity through MnSe and MnTe₂ crystalline phases with an increase in Se/Te ratio is confirmed by the structural study. The existence of different vibrational modes in the sample with alteration in the microstructural region is confirmed by a Raman study. The morphology study shows the nanosheet (nSh) structure as formed for the as-prepared MST samples, confirming the formation of 2D nanomaterial. The nSh thickness gradually decreased with a decrease in the Se concentration and increased Te. The reduction of the optical band gap of nSh is reflected by shifting the absorption edge to a higher wavelength regime. The refractive index values lie between 2.14 and 2.78 for different MST nSh as per theoretical calculation. The presence of various exothermal and endothermal peaks is confirmed by thermal analysis for the present sample. These materials undergo photodetection measurement, where they illustrate commendable responsivity across a range of values: 1.73, 8.88, and 28.88 nA W^–1. Additionally, these materials showcase detectivity at levels of 1.14 × 10¹⁰, 2.52 × 10¹⁰, and 3.96 × 10¹¹ Jones, respectively. The changes in different optical and structural parameters enable the material’s applicability in optoelectronic devices.