Sequential growth-controlled silver selenide nanoparticles embedded 1D-CdS nanowires: Heterostructure design to enhance power conversion efficiency

Room temperature sequential growth namely, successive ionic layer adsorption and reaction (SILAR) method has been successfully processed towards the controlled growth of silver selenide (Ag2Se) nanoparticles onto one dimensional (1D) CdS nanowires (NWs) array. Well controlled size tuning enables well-aligned heterostructure yielding almost four times enhancement (0.34%) in power conversion efficiency compared to the bare CdS NWs (0.09%) in photoelectrochemical (PEC) solar cell assembly. Results are well equipped through structural, surface morphological, optical and elemental oxidation state in correlation with PEC solar cell, external quantum efficiency (EQE), Mott-Schottky (M - S), and electrochemical impedance spectroscopy (EIS) performances. Interestingly, sequential SILAR method produces extremely conformal coverage of Ag2Se layer with precise thickness control. The optimum mutualistic contribution from Ag2Se and CdS not only broaden the light absorption range but also allows the rapid separation of excited charge carriers at heterostructure interface.

Automated summary

In this study, the room temperature sequential growth method (SILAR) was successfully used to control the growth of silver selenide nanoparticles on one-dimensional CdS nanowires. The well-aligned heterostructure achieved through size tuning and thickness control significantly enhanced the power conversion efficiency. The correlation between the performance of the photoelectrochemical solar cell and the structural, surface morphological, optical, and elemental oxidation state properties was well established.