Environment-friendly High Efficiency CH3NH3PbI3 Perovskite Solar Cells Fabricated by Green Antisolvent Method

Green antisolvents propyl acetate and isooctane can promote the nucleation of PbI2 particles and provide the heterogeneous nucleation site of perovskite crystal, so as to promote the rapid growth of perovskite crystal. The films treated with propyl acetate and propylene glycol methyl ether have larger grains and lower root-mean-square value (RMS) than those treated with chlorobenzene. The full coverage perovskite films with uniform grain size which is closer to the exciton diffusion length of perovskite can be obtained. Compared with the CH3NH3PbI3 perovskite solar cells treated with chlorobenzene (power conversion efficiency (PCE) is 17.86%), the best efficiency of the devices treated with propylene glycol methyl ether is 21.60%, which is improved by 21%, which has certain reference value and guiding significance for researchers to obtain environment-friendly high-quality perovskite solar cells in the future.

Benzenesulfonic Acid - an Green Efficient Esterification Catalysts for Continuous Synthesis of n-propyl Acetate

The esterification of acetic acid and n-propanol catalyzed by benzenesulfonic acid and its derivatives in the batch and continuous rectification tower was studied, in order to develop a new effective and green catalyst instead of the oxidative and corrosive sulfuric acid. A series of the comparison system with sulfuric acid was build for the targeted and fast evaluation of catalysts. The results showed that the catalytic esterification activity of p-phenolsulfonic acid and p-toluenesulfuric acid is very closed to sulfonic acid in the continuous rectification tower. Furthermore, the stability test for continuous esterification with p-toluenesulfuric acid presented that the high yield of n-propyl acetate could maintain 50 hours and stability. Therefore, p-phenolsulfonic acid and p-toluenesulfuric acid could be prospective substitutes for sulfuric acid for the continuous synthesis of n-propyl acetate in the rectification tower.