Non-noble metal sulfides are layered materials with graphene-like structure, which have good applications in catalysis, microelectronics, semiconductor and other fields. Tungsten sulfide and molybdenum sulfide catalysts have been used as hydrogenation catalysts in petroleum processing. They are widely used in hydrodesulfurization, hydrodenitrification, hydrodearomatization, hydrodeoxygenation and hydrodemetallization.

In order to ensure the uniformity of the dispersion of the composite particles and to improve the properties of the materials to the greatest extent, it is often required that the doped phase particles be coated on the surface of the matrix particles to form a coating to achieve the best mixing degree.

As the main transition metal selenide, tungsten diselenide (WSe₂) is a kind of engineering material and functional material with many special properties. WSe₂ crystal has a hexagonal sandwich structure similar to MoS₂. Each WSe₂ molecule layer is composed of two Se atom layers with a W atom layer. The W atom layer and Se atom layer are covalently bonded, while the adjacent WSe2 layers are separated by Se layer with a long distance and a weak van der waals force.

Suspension bed hydrogenation is an advanced technology for preparing liquid fuel oil from heavy unconventional oil. Suspension bed hydrogenation process requires catalyst with high activity, high dispersibility, high stability and good economy. Tungsten sulfide and molybdenum sulfide catalysts have been used as hydrogenation catalysts in petroleum processing. They are widely used in hydrodesulfurization, hydrodenitrification and other reactions. They are very promising catalysts for heavy oil hydrogenation in suspension bed process to produce clean fuel.