Tungsten oxide is an n-type semiconductor and is a typical transition metal oxide. As a functional material, it is applied to industrial catalysts, electrochromic, battery electrodes, solar energy absorbing materials, invisible materials, gas sensing materials, and the like. Especially in the field of oxide semiconductor gas sensor applications, tungsten oxide-based materials have been considered as one of the most promising new oxide gas sensing materials for detecting NOx, SOx, NH3 and H2S.

Nanomaterials refer to materials whose dimensions reach the nanometer scale in a certain dimension, two-dimensional or three-dimensional direction. It can be divided into zero-dimensional materials, one-dimensional materials, two-dimensional materials, three-dimensional materials. When a conventional material reaches the nanometer scale, its properties will be very different from usual.

Infrared light, especially near-infrared, has a significant thermal effect, which tends to cause temperature rise, which causes an increase in temperature, such as indoors or in a car. The currently disclosed infrared barrier materials generally refer to a class of functional materials that have a strong absorption or reflection of infrared light without affecting the transmission of visible light.

Magnetron is currently the most efficient microwave device, and it has a huge application market in the fields of civil heating and radiology. In recent years, with the rapid growth of microwave application markets such as radiology and container inspection, magnetrons continue to develop in the direction of high power, high frequency, miniaturization and low cost.