Photoexcitation and radiation regulation mechanism of Ag anchoring WSe2 heterojunction with plasma coupling effect

The noble metal silver (Ag) combined with tungsten selenide (WSe2) was used to solve the problems of the narrow absorption band range, low luminescence quantum yield, and nonlinear transmittance of WSe2 base materials. Ag/WSe2 films and core–shell [email protected]2 heterojunction were designed and fabricated by the two-step magnetron sputtering and hydrothermal/magnetron sputtering method, respectively. X-ray diffraction, scanning electron microscopy and X-ray photoelectric spectroscopy results confirmed that the successful preparation of Ag/WSe2 and [email protected]2. Raman results demonstrate the presence of interfacial stress between Ag and WSe2. Based on quantum particle coupling in metal–semiconductor nanocomposites, the adsorbed silver particles provide electrons and through charge transfer, which increases the density of electronic states in conduction band of the WSe2 and thus increases the spontaneous emission rate. Electron-hole pairs generated in the semiconductor through resonant coupling between surface plasmas of the Ag and WSe2 interface will provide strongly enhanced radiative recombination. The absorption and emission of WSe2 nanosheets in the visible light range and linear-nonlinear optical properties depend on the regulation the sputtering power and pressure of Ag particles. Our research results demonstrate that Ag&WSe2 have excellent optical and photoelectric properties, indicating that Ag&WSe2 have a wide application potential in photoelectric functional and optoelectronic devices.