Spray-Deposited NiCo2S4 Based Materials As Counter Electrodes For Dye-Sensitized Solar Cells

• Main Authors: Man-Ning Lu, 呂曼寧
• Other Authors: Jeng-Yu Lin
• Format: Others
• Language: en_US
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/q3xc25

碩士 === 大同大學 === 化學工程學系(所) === 102 === In this study, NiCo2S4 was synthesized via a facile hydrothermal method by nickel chloride hexahydrate, cobalt chloride hexahydrate, and thiourea in aqueous solution and then reacting at 240℃, 12h. Subsequently, reduced graphene oxide (RGO) was synthesized by chemical exfoliation and hydrothermal reduction treatment. In the hybrid NiCo2S4/RGO materials, the different ratios (2, 5, 10 wt%) of RGO sheets were mixing with NiCo2S4 particles in ethanol. According to X-ray diffraction (XRD), Raman spectrum, and scanning electron microscope (SEM) confirmed that the NiCo2S4 particles and RGO were successfully synthesized and mixed homogeneous. As a result, the ratio of RGO hybrid into NiCo2S4 particles could be effectively controlled, which is crucial for RGO achieving of high electron transfer and electrocatalytic activity of NiCo2S4 particles compared to the conventional Pt counter electrode (CE). Therefore, the dye-sensitized solar cell (DSSC) assembled with hybrid NiCo2S4/RGO-2wt% exhibited the highest catalytic activity and the best conductivity. Moreover, the NiCo2S4/RGO-2wt% CE demonstrated an impressive lower electrode/electrolyte charge-transfer resistance (Rct 0.35 Ω). Also, the DSSC using NiCo2S4/RGO-2wt% as CE offered outstanding power conversion efficiency of 8.04%, which is much higher than NiCo2S4 (7.03%) and Pt (7.80%) CEs.