Recycling of Compound Semiconductor Photovoltaics by Means of Ambipolar Eletrolysis

Problem: -Toxicity and environmental impact of Cd and Te, which is widely used in thin film solar cells -Multiple steps required by current recycling methods Technology: The invention provides a new method to recycle compound semiconductor materials used in the photovoltaic industry using ambipolar electrolysis (AE). The proposed process selectively dissolves the semiconductor material off of the solar cell into a molten salt bath, leaving behind the glass and metal wire contacts. AE can then be performed on the molten salt containing the dissolved compound, resulting in the simultaneous electro-deposition of the two metals onto separate electrodes. To recycle CdTe, the molten salt can be CdI2 or CdCl2-KCl, and the operating temperature is at 500。C. Given the high purity of the collected molten metals, Cd and Te products could be remixed under N2, producing CdTe, ready to be reintroduced into the manufacturing stream of new solar cells. Christopher Noble crn@mit.edu