Environmental-friendly CuInS2 Quantum dots-Sensitized Solar Cell

• Main Authors: Chia-Chan Chang, 張嘉展
• Other Authors: Jia-Yaw Chang
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/96184028756556012458

碩士 === 國立臺灣科技大學 === 化學工程系 === 101 === A cadmium metal-free CuInS2 quantum dot (QD)-sensitized solar cell (QDSSC) has been fabricated by taking advantages of the ex-situ synthesized approach with high crystalline of QDs and in-situ successive ionic-layer adsorption and reaction process (SILAR) approach with high surface coverage of QDs. The ex-situ synthesized CuInS2 QDs can be rendered water-soluble through simplicity and rapidity two-step method under the assistance of ultrasonication. This approach allows a stepwise ligand change from the foreign ligand insertion to ligand replacement, which preserves long-term stability of colloidal solution more than one month. Furthermore, the resulting QDs can be exploited as sensitizer in QDSSC delivered a power conversion efficiency (PCE) of 0.64%. Following by using the SILAR process, the in-situ CuInS2 could be epitaxial growing on the pre-existing seeds of ex-situ synthesized CuInS2 QDs. The results indicated that the CuInS2 QDSSC fabricated by the combined ex-situ/in-situ growth exhibited PCE of 1.84% (Jsc = 7.72 mA/cm2, Voc = 570 mV, and FF = 41.8%), which is higher than those of CuInS2 QDSSC formed by ex-situ and in-situ growth, respectively. The photon-to-current conversion efficiency and electrochemical impedance spectroscopy have been carried out to substantiate photovoltaic behavior and the charge-transfer resistance. The results suggest that the combined synergetic effects of in-situ and ex-situ CuInS2 QD growth facilitating higher electron-injecting efficiency from the QD sensitizers into the TiO2.