Synthesis of copper sulphide nanoparticles for solar cells applications

• Main Author: Tan, Pei Keng.
• Other Authors: Lam Yeng Ming
• Format: Final Year Project
• Language: English
• Published: 2010
• Subjects: DRNTU::Engineering::Materials::Nanostructured materials
• Online Access: http://hdl.handle.net/10356/35689
• Institution: Nanyang Technological University

There has been an increase in interest lately to explore the possibility of using hybrid system in solar cells. The reason for this is because of its low cost potential and scalability. This report will discuss on the synthesis of monodisperse copper sulphide (Cu2S) nanoparticles for the application in hybrid solar cells. Monodisperse Cu2S nanospheres of diameter 5 nm were obtained successfully by using the hot coordinating solvent method. Using the same synthesis method, a mixture of nanosphere, nanorods and nanowires can also be obtained. Their dimensions are 50 nm, 50 x 200 nm and 50 x 500 nm respectively. Different surfactants, including ODPA, MA, OLA and DLA, were used to synthesize Cu2S nanoparticles. The coordinating systems were also done with different mole ratio, reaction time and reaction temperatures. The morphologies of nanoparticles obtained from transmission electron microscopy (TEM) can be tuned by varying the reaction parameters. This in turn it changes the optical characteristics which can be observed using ultraviolet-visible (UV-Vis) spectroscopy. X-ray diffraction (XRD) pattern obtained from the Cu2S have sharp (110) peak. The solar cell was fabricated using Cu2S as an acceptor and P3HT as a donor. The results shown from the power conversion efficiency (PCE) and incident photon conversion efficiency (IPCE) test were undesirable. The main reasons were possibly due to the ligand, OLA, used was non-conducting and no optimization of solar cell was done due to lack of time. Other possible reasons would be due to the incomplete percolation of the nanospheres network for charge transfer, and having poor contact in the interfacial areas between particles and polymer resulting in reduction in charge separation.