Bi-functional lithium doping in dye-sensitized solar cells

摘要

Despite intensive research into dye sensitized solar cells (DSSCs), simultaneously increasing both the short-circuit photocurrent density (J_(sc)) as well as open-circuit photovoltage (V_(oc)) of cells has thus far proven impossible. This paper reports the fabrication of Li-doped NiO electrodes to investigate a bi-functional mechanism in which Li enhances light absorption, suspends electron-hole recombination, and reduces the electrical resistivity of the electrode. We also outline the optimization of sol-gel synthesis and investigate the performance of the developed DSSCs. Our results reveal a 6.8% increase in V_(oc) as well as a 24.7% increase in J_(sc), compared with a DSSC with TiO_2 electrode. The proposed mechanism, based on state-of-the-art electronic structure theory, provides a valuable guide for the further development of solar cells and electrochemical devices in general.