Unique Cation Exchange in Nanocrystal Matrix via Surface Vacancy Engineering Overcoming Chemical Kinetic Energy Barriers

Summary Surface vacancy engineering played a significant role in tailoring the structure and improving the performance of semiconductor nanocrystals (SNCs). Developing controllable vacancy engineering strategies to overcome kinetic energy barriers in multi-step reactions is anticipated to explore further synthesis mechanisms and functional nanomaterials. Herein, we exploited an effective surface-vacancy-engineering-initialized cation exchange (SVEICE) strategy to realize energy-unfavored cation exchange reactions from ternary CuInX2 (X = S, Se) to Cu, In dual-doped binary CdX, or ZnX SNCs, unprecedentedly. The sequential and selective creation of Cu and In vacancies on multi-component SNC surface is critical to break through kinetic energy barriers. The emission of dual-doped CdS:Cu/In SNCs crossed visible-NIR region due to the radiative transition from doped In level to Cu-doped e- or t-level, and the radiative recombination process could also be tailored by this strategy. Further energy analysis and experiments confirmed its versatility.