Preparation of Cu2ZnSn(S,Se)4 thin film solar cells by a green and facile solution method

In this research, a green and facile solution was reported by using ethylene glycol as solvent into Cu2ZnSn(S,Se)4 thin films. Highly crystallized CZTSSe thin films without obvious impurity phases were obtained. We found that the carbon chains length of solvent has a notable influence on the of grain size distribution. Comparing the film obtained with 2-methoxyethanol solvent, CZTSSe thin film based on ethylene glycol had a thinner fine grain in the bottom layer and larger grains in the top layer. In addition, the CZTSSe thin film solar cell from ethylene glycol showed an obvious collection ability enhancement and an enhanced conversion efficiency by 45% than that from 2-methoxyethanol.