An 8.2% efficient solution-processed CuInSe2 solar cell based on multiphase CuInSe2 nanoparticles

Multiphase CuInSe2 (CISe) nanoparticles including the CuSe phase are synthesized by the microwave-assisted solvothermal method. Without additional processing, multiphase CISe nanoparticles facilitate the solution-processed CISe absorber layer with a dense microstructure, large grains, high crystallinity, and composition controllability, which are essential for acceptable thin-film solar cell performance. The high performance, solution-processed CISe solar cell, with a conversion efficiency of 8.2%, is obtained through phase transformation, microstructural evolution, and composition adjustment by selenization (annealing under a Se atmosphere) at 530 °C.