In recent years, flexible perovskite solar cells have attracted much attention, and the flexible substrates used have a great impact on the performance of devices. At present, the commonly used flexible substrates of polyethylene terephthalate (PET) and metal foil can not meet the demand. It is urgent to find a cheap and abundant new flexible substitutes.

At present, tungsten trioxide has been used in many aspects of daily life, such as the manufacture of X-ray phosphors, refractories and gas sensors. In addition, tungsten trioxide has an important application field, namely photocatalytic degradation materials.

Tungsten oxide is a new functional material, which can be used in chemical sensors, catalytic materials, electrochemical electrodes, electrochromic materials, high temperature superconducting materials, solar energy absorbing materials, wave absorbing stealth materials and so on.

Ultrafine cemented carbide is a tool material developed in recent years. It is mainly based on ultrafine tungsten carbide powder and adds appropriate binder (such as Co) and grain growth inhibitor to produce high hardness, high wear resistance and high toughness cemented carbide material. Its performance is higher than conventional cemented carbide. It is used in hard-to-machine metal materials tools, micro-drills in electronic industry, precision dies and dies. Medical dental drills and other fields have shown more and more extensive application prospects.