How is antimony trisulfide used beyond flame retardants, and which new demand sectors matter?

How is antimony trisulfide used beyond flame retardants, and which new demand sectors matter?
Antimony trisulfide (Sb2S3) is far more than a flame retardant additive. In fireworks, it acts as an oxidizer and fuel, helping produce bright white light and controlling burn trajectories—poor-quality or damp material causes duds. More strategically, it is a direct bandgap semiconductor used in thin-film solar cells, photodetectors, resistive memory and X-ray imaging. Its bandgap of 1.3–1.9 eV and high absorption make it a candidate for low-cost, lead-free photovoltaic absorbers, including tandem perovskite-antimony devices. This 'photovoltaic metal' narrative is gaining traction, with analysts projecting antimony consumption growth of 29–62% across flame retardants, batteries, polyester catalysts and military applications during China's 14th Five-Year Plan period.