Volatile organic solvents sensing using silicon nanowires array fabricated by spontaneous electrochemical reaction

In order to prevent overexposure to volatile organic solvents (VOCs), a simple sensing device with high sensitivity is needed in the common workplace. Meanwhile, silicon nanowires carrying the high surface-bulk ratio as a unique characteristic could be used for VOCs sensing. This study utilised spontaneous electrochemical reaction, which involves etching of silicon wafer in a silver nitrate and hydrofluoric acid based solution, to modify etching times for silicon nanowires fabrication. This research discovered that the length of nanowire increased and VOCs sensing sensitivity improved as the etching time increased. Furthermore, diethyl ether had the optimal performance on the effect of silicon nanowires array on VOCs sensing. The study also discussed the effect of VOCs molecules and electron distribution on silicon nanowires surface, to further investigate the impact on sensing sensitivity.