Size‐Tunable Synthesis of Colloidal Silver Sulfide Nanocrystals for Solution‐Processed Photovoltaic Applications

Abstract

Abstract Silver sulfide (Ag 2 S) quantum dots (QDs) exhibit promising candidature for low‐cost solution‐processed photovoltaic devices due to its narrow band gap, high optical absorption coefficient, and being composed of environment friendly materials. In this work, we have synthesized a series of different sized and nearly monodispersed Ag 2 S quantum dots by using thioacetamide as sulfur source at relatively low temperature (< 100 °C). Transmission electron microscopy and X‐ray diffraction studies suggests that the as‐synthesized QD S are nearly monodisperse and highly crystalline. The optical band gap and energy levels of valence and conduction bands were determined by absorption and ultraviolet photoemission spectroscopy, respectively. A hybrid solar cell based on blends of poly (3‐hexylthiophene) and Ag 2 S QDs were fabricated and tested for photovoltaic application. The results indicate that Ag 2 S QDs are promising material for the fabrication of low cost and environment friendly polymer‐QDs hybrid optoelectronics devices.