Structure and photoelectrochemical properties of silicon microstructures arrays

Two silicon microstructrues of silicon nanowires (SiNWs) and silicon microchannel plates (Si MCP) have been successfully fabricated combined by standard microelectronics technology and electrochemical method. The performances have been investigated for dye-sensitized solar cells (DSSCs) by applying silicon nanowires (SiNWs) and silicon microchannel plates (Si MCP) to the counter electrode, respectively. And the electrocatalytic activities of Si MCP and SiNWs electrodes for triiodide reduction were studied using electrochemical impedance spectroscopy. The two microstructure electrodes consisting of a large number of channels with high surface to volume ratio exhibits a highly interconnected network structure with good catalytic activity. A high photovolatic conversion efficiency of over 7.01% and 7.86% were recorded for DSSCs based on the Si MCP and SiNWs counter electrodes, which is comparatable to the cell based on conventional Pt counter electrode at the same condition. It could be expected that this low cost SiNWs and Si MCP and compatibility with microelectronic technology would make the silicon-based monolithic DSSC available in practical application.