Engineering Halide Perovskites With Chalcogen‐Based Compounds: Insights Into Stability, Interfaces, and Device Integration

ABSTRACT Halide perovskites have emerged as next‐generation semiconductors for solar cells, light‐emitting diodes (LEDs), and photodetectors owing to their exceptional optoelectronic properties and solution processability. However, their commercialization is hindered by poor chemical and structural stability under moisture, oxygen, heat, and illumination. Chalcogen‐based compounds, comprising oxygen, sulfur, selenium, and tellurium derivatives, offer a versatile chemical platform to overcome these limitations through defect passivation, interface stabilization, and lattice reinforcement. This review systematically examines the mechanistic roles of chalcogen–metal and chalcogen–halide interactions in governing defect chemistry, ion migration, and degradation pathways in perovskite materials. Particular emphasis is placed on the chemical bonding principles, interfacial energetics, and structure–property correlations that underpin chalcogen‐mediated stabilization. The integration of chalcogenides as surface modifiers, grain boundary fillers, or interfacial layers is critically assessed across perovskite solar cells, LEDs, and photodetectors, highlighting advances in device efficiency and durability. From a chemical engineering perspective, scalable synthetic approaches, such as vapor‐phase sulfidation, solution‐based ligand exchange, and hybrid perovskite–chalcogenide heterostructure fabrication, are discussed with respect to process control, energy efficiency, and environmental safety. The review concludes with emerging directions for designing multifunctional chalcogen systems compatible with large‐area coating, green manufacturing, and industrial deployment of stable perovskite optoelectronic technologies.