Colloidal Photodetectors Based on Engineered Multishelled InP Based Quantum Dots

Abstract

In this work, we present a straightforward and cost-effective approach to synthesize multi-shell InP/ZnSe/ZnSeS/ZnS quantum dots (QDs) that show promising potential for use in photodetectors. By carefully layering ZnSe, ZnSeS, and ZnS shells around an InP core, we were able to enhance the stability and optical performance of the QDs, achieving a narrow emission peak of 45 nm and a high photoluminescence quantum yield of 55%. These QDs were then integrated into simple photodetector devices, which possessed impressive sensitivity and detection capabilities. Specifically, our devices achieved a peak responsivity of 0.54 A W-1 and a detectivity of 2.22 x 1011 Jones at 400 nm with a 5 V bias. This study highlights the potential of InP-based QDs as a safer and more sustainable alternative to traditional QDs that contain toxic heavy metals, offering a viable path forward for developing high-performance optoelectronic devices. Our findings suggest that these InP/ZnSe/ZnSeS/ZnS QDs could be a key material for the next generation of high-performance optoelectronic devices, especially in applications that require highly sensitive and stable photodetectors.