An exhaust gas purification apparatus and method is applied to an internal combustion engine. The first chamber of the apparatus further includes a collecting surface for attracting the spray droplets, a power supply, and a spray nozzle connected to the power supply for receiving fluid and producing the spray droplets therefrom. The sensor panel may dynamically reconfigure its sensor size and shape based on an object’s proximity to the panel. The tin-containing metal oxide nanoparticles and their dispersion disclosed herein may be applied on the window glass of houses, buildings, vehicles, ships, etc. Furthermore, the valve body has an integral structure.