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The remarkable optoelectronic properties and considerable performance of the organo lead‐halide perovskites (PVKs) in various optoelectronic applications grasp tremendous scientific attention. However, the existence of the toxic lead in these compounds is threatening human health and remains a major concern in the way of their commercialization. To address this issue, numerous nontoxic alternatives have been reported. Among these alternatives, bismuth‐based PVKs have emerged as a promising substitute because of similar optoelectronic properties and extended environmental stability. This work communicates briefly about the possible lead‐alternatives and explores bismuth‐based perovskites comprehensively, in terms of their structures, optoelectronic properties, and applications. A brief description of lead‐toxification is provided and the possible Pb‐alternatives from the periodic table are scrutinized. Then, the classification and crystal structures of various Bi‐based perovskites are elaborated on. Detailed optoelectronic properties of Bi‐based perovskites are also described and their optoelectronic applications are abridged. The overall photovoltaic applications along with device characteristics (i.e., V OC , J SC , fill factor, FF, and power conversion efficiency, PCE), fabrication method, device architecture, and operational stability are also summarized. Finally, a conclusion is drawn where a brief outlook highlights the challenges that hamper the future progress of Bi‐based optoelectronic devices and suggestions for future directions are provided.

Multiphonon resonant Raman scattering in N-doped ZnO films was studied, and an enhancement of the resonant Raman scattering process as well as longitudinal optical (LO) phonon overtones up to the sixth order were observed at room temperature. The resonant Raman scattering intensity of the 1LO phonon in N-doped ZnO appears three times as strong as that of undoped ZnO, which mainly arises from the defect-induced Raman scattering caused by N-doping. The nature of the 1LO phonon at 578 cm −1 is interpreted as a quasimode with mixed A 1 and E 1 symmetry because of the defects formed in the ZnO lattice. In addition, the previously neglected impurity-induced two-LO-phonon scattering process was clearly observed in N-doped ZnO.

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