Micro‐Flame‐Induced Grain Boundary Reconstruction for Highly Stable and Efficient Carbon‐Based CsPbBr3 Perovskite Laser Cells

Choosing the appropriate laser‐electrical converter in laser power transmission (LPT) technology is crucial. However, the laser‐electrical converter in LPT technology remains largely unexplored, particularly in perovskite cells. CsPbBr3 perovskite demonstrates excellent stability against moisture, radiation, and heat. Moreover, owing to the wide bandgap of CsPbBr3, the devices utilizing this absorber demonstrate high open‐circuit voltage, making them suitable for carbon‐based perovskite laser cells (C‐PLCs). In this study, we introduced p‐type CuSCN nanocrystals as the modifier of CsPbBr3 and proposed a simple method for constructing CuSCN‐CsPbBr3 gradient hybrid films. It is noteworthy that the flammability of CuSCN facilitates micro‐flame‐induced surface recrystallization and grain boundary reconstruction during the annealing process. As expected, the crystallinity and absorbance intensity of the photo‐responsive layer were optimized. The trap states were passivated, and carrier transport and extraction were accelerated. Consequently, the photovoltaic performance of C‐PLCs was enhanced by embedding CuSCN into CsPbBr3. What is particularly exciting is that the C‐PLCs modified with CuSCN exhibit an impressive power conversion efficiency of 56.57% and a high open‐circuit voltage of 1.52 V. This shows that C‐PLCs utilizing a CuSCN‐CsPbBr3 hybrid film exhibit significant potential for use in LPT technology.