Influence of Gold-Selenium Precursor Ratio on Synthesis and Structural Stability of α- and β-AuSe

Abstract: Gold selenide (AuSe) is a multilayer compound yet to be thoroughly studied. The colloidal synthesis and characterization of gold selenide nanoparticles are described, emphasizing the effect of different gold-to-selenium precursor ratios and temperatures on the crystal structure and form. The structural characterization is done using an X-ray diffraction pattern. The coexistence of the {\alpha}- and {\beta}-AuSe phases is observed in all synthesized samples. The morphologies of the mainly {\alpha}-AuSe sample are nanobelts, whereas the primarily {\beta}-AuSe phase sample has a nanoplate-like structure, according to the TEM and SEM data. All of the samples had Raman vibrational modes with mixed phases. The effect of high pressure on as-prepared AuSe samples has been studied in this work. The introduction of external pressure and temperature allows both phases to transition. Pressure lowers the existence of other phase modes, and the corresponding dominating sample modes are entirely significant in our sample. The phase transition pressure was observed using Raman scattering. Our findings show that 2D AuSe has a lot of promise for multifunctional applications, encouraging more research on these systems.