Silver–bismuth perovskite-inspired materials: chemistry, optoelectronic properties, and emerging applications in photovoltaics and beyond

under indoor lighting), alongside unique functional properties, such as pronounced second-harmonic generation, broadband photocatalysis, resistive switching for neuromorphic devices, and high-sensitivity X-ray detection. Emerging insights reveal that homogeneous CD can reduce bandgaps and enhance light absorption, while controlled crystal vacancies induce local structural modifications critical for nonlinear optical responses. By systematically linking the atomic-scale structure to photophysical behaviour and device-level performance, this review traces clear design guidelines-such as enhancing the ED, minimizing deep trap states, and leveraging mixed-anion chemistry-to advance Ag-Bi PIMs from promising lead-free absorbers to versatile platforms for sustainable energy, photonics, and intelligent electronics. We propose a roadmap outlining a three-stage development model focused on material innovation and device optimization for system-level integration, positioning Ag-Bi PIMs as environmentally friendly semiconductors with broad potential in next-generation optoelectronics.