Semi Transparent Photovoltaic Cell
Tan, Clarice Yee Zhen
Date of Issue2017
School of Materials Science and Engineering
Climate change is deteriorating and leading to a phenomenon of energy crisis. Measures were taken to reduce traditional fuel use which include increasing energy efficiency and finding alternative source. Many methods have been used to reduce energy wastage by finding alternative sources, energy saving campaigns as well as one direct key step in reducing carbon emission is the building green initiatives where buildings (e.g commerce, hotels and residence) are integrated with technologies to help in energy saving. In this project, we attempt to investigate the possibility of producing a semi-transparent solar cell using solution process approach for building integrated photovoltaic (BIPV) application. As solution process is cheap and easily scaled-up, the purpose is to attempt to explore a cheap and easy method to produce semi-tranparent cell in window application and as an alternative energy source. The aim is to provide both cooling effect and electricity generation for the building use. The approach is to use Cu2ZnSnS4 (CZTS ) as the solar absorbing material due to the abundance of the element. Stainless steel mesh and fluorine-doped tin oxide (FTO) glass were investigated as plausible transparent substrates. In this report, various solution processes was attempted: 1) spray pyrolysis, 2) draw down method and 3) spin coating, to find the most effective way to fabricate semi- transparent absorber layer. Characterization of the crystal structure and phase purity of the thin film are carried out using EDX, XRD and Raman, while the film thickness and optical properties are characterized by UV-Vis and SEM. It is realised that fabricating of semi-transparent CZTS solar cell using spin coating is proven to be the most effective approach. As FTO substrate is used, the tin content in the ink has to be reduced due to diffusion of Sn from FTO to CZTS layer, next the solvent has to be changed to a coordinating solvent (such as DMF) to stabilize the ink. With optimization done, we managed to get a working semi-transparent device with 0.28 % efficiency.
Final Year Project (FYP)
Nanyang Technological University