ZnS-coated Yb3+-doped perovskite quantum dots: A stable and efficient quantum cutting photon energy converter for silicon-based electronics

Yb3+ doped lead halide perovskite quantum dots (PeQDs) with efficient quantum cutting emission are thought to be the most promising photon energy converter for improving the performance of silicon-based electronics. Nevertheless, the low external quantum efficiency (EQE) and instability make it unfeasible for industrial use. Here, we present a unique PeQDs@ ZnS core–shell device that achieves outstanding stability and up to 39 % EQE by effectively controlling energy transfer from the PeQDs to the Yb3+ through ZnS coating. These advances are attributed to the large UV absorption and the strong localized effect of the ZnS shells on the conduction band electrons of the PeQDs. Density functional theory (DFT) first-principles simulations indicate that ZnS coating can facilitate the energy transfer of PeQDs to Yb3+. Power conversion efficiency (PCE) of silicon solar cells was significantly enhanced by ZnS-coated Yb3+ doped PeQDs, yielding a noteworthy 13.5 % relative PCE improvement over 30 measurement sets. Significantly, the stability of SSCs with ZnS-coated PeQDs films is considerably improved, resulting in a capped device T80 lifespan of up to 11,224 h. Moreover, ZnS-coated PeQDs films can significantly boost the EQE of silicon photodiodes (Si-PDs) and extend their response to deep ultraviolet light. This paper presents an efficient and consistently stable photon energy converter with great commercialization potential.