A composite multi-cation high-entropy catalyst, which integrates the concept of high-entropy compounds into traditional metal oxide catalysts, such as spinel, perovskite, and fluorite structure. By the combination of photoelectric, piezoelectric, and ferroelectric materials with the characteristic high-entropy oxides. The high-entropy composite piezoelectric catalysts could become a promising technology for clean energy applications, such as organic dye degradation and hydrogen generation.