Kipkorir Anthony, Chen Bo-An, Kamat Prashant V
Radiation Laboratory, University of Notre Dame, Notre Dame, Indiana 46556, United States.
Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States.
ACS Nano. 2024 Oct 15;18(41):28170-28177. doi: 10.1021/acsnano.4c07774. Epub 2024 Oct 1.
Accurate tuning of the electronic and photophysical properties of quantum dots is required to maximize the light conversion efficiencies in semiconductor-assisted processes. Herein, we report a facile synthetic procedure for AgIn(SSe) quantum dots with S content () ranging from 1 to 0. This simple approach allowed us to tune the bandgap (2.6-1.9 eV) and extend the absorption of AgIn(SSe) quantum dots to lower photon energies (near-IR) while maintaining a small QD size (∼5 nm). Ultraviolet spectroscopy studies revealed that the change in the bandgap is modulated by the electronic shifts in both the valence band and the conduction band positions. The negative overall charge of the as-synthesized quantum dots enabled us to make films of quantum dots on mesoscopic TiO. Excited state studies of the AgIn(SSe) quantum dot films demonstrated a fast charge injection to TiO, and the electron transfer rate constant was found to be 1.5-3.5 × 10 s. The results of this work present AgIn(SSe) quantum dots synthesized by the one-step method as a potential candidate for designing light-harvesting assemblies.
为了在半导体辅助过程中实现光转换效率最大化，需要精确调节量子点的电子和光物理性质。在此，我们报道了一种简便的合成方法，用于制备硫含量（）范围为1至0的AgIn(SSe)量子点。这种简单的方法使我们能够调节带隙（2.6 - 1.9 eV），并将AgIn(SSe)量子点的吸收扩展到更低的光子能量（近红外），同时保持较小的量子点尺寸（约5 nm）。紫外光谱研究表明，带隙的变化是由价带和导带位置的电子位移调制的。合成的量子点的负总电荷使我们能够在介观TiO上制备量子点薄膜。AgIn(SSe)量子点薄膜的激发态研究表明，电荷快速注入到TiO中，电子转移速率常数为1.5 - 3.5×10 s。这项工作的结果表明，通过一步法合成的AgIn(SSe)量子点是设计光捕获组件的潜在候选材料。
