Natural and Nature‐Inspired Biomaterial Additives for Metal Halide Perovskite Optoelectronics

This comprehensive review meticulously categorizes and discusses the applications of diverse biomaterials, specifically natural and nature‐inspired synthetic materials in metal halide perovskite optoelectronics. Applications range from solar cells to light‐emitting diodes, photodetectors, and X‐ray detectors. Emphasis is placed on the intricate interactions between bio‐additives and perovskite crystals, highlighting their influence on the grain size, crystal orientation, grain boundaries, and surface passivation. This review also explores the advantages and disadvantages of each natural or nature‐inspired material and their unique properties compared with conventional additives. Special attention is given to the mechanistic and functional viewpoints, showing how these biomaterials enhance device performance. Through additive engineering with ecofriendly biomaterials, defects in metal halide perovskite thin films can be effectively passivated, thus extending the photostability or in some cases mechanical flexibility of devices. This review provides valuable insights for selecting and designing next‐generation biomaterial additives, offering new prospects for achieving high‐performance perovskite layers and advancing the field of peorvskite‐ based optoelectronics.