Size- and Surface-Dependent Solubility of Cadmium Telluride in Aqueous Solutions

Due to the toxicity of cadmium (Cd) and scarcity telluride (Te), CdTe-based photovoltaic modules have been under discussion during last few years. In particular, stability CdTe in aqueous solutions is debate. Here we show that depends not only on pH water-based but also size surface treatment particles. We compare milled module pieces with powders different particle size. The leaching conditioned by outdiffusion Cd Te at interface between particles solution. smaller size, faster leaching. Therefore, decompose than relatively large grains. observe a dependence time t according t0.43. room temperature diffusion coefficients are calculated as DCd ≈ 3 × 10−17 cm2/s for Cd, DTe 1.5 pH4. chemical instability follows thermodynamic considerations. solution behavior value redox potential solutions. Chemical treatments such those used solar cell production modify their behavior.