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. 

The composite high-entropy piezoelectric catalyst has multiple characteristics such as photoelectric, piezoelectric, and ferroelectric properties. Owing to the severe lattice distortion effect of high entropy oxides, the non-centrosymmetric structure was created to form ferroelectric crystals that were highly dispersed in the porous high-entropy oxide. The ferroelectric structures localized at the interfaces of grain boundaries, which can effectively separate electron and hole pairs and inhibit recombination under the application of mechanical force, leading to the high-entropy piezoelectric catalyst can effectively improve the degradation characteristics of organic pollutants.

The composite high-entropy piezoelectric catalyst uses a wet chemical synthesis process, which can be manufactured in large quantities and has high economic benefits. The composite high-entropy piezoelectric catalyst has multiple cations and piezoelectric (or ferroelectric properties) characteristics, which makes the catalyst activity much higher than traditional catalysts (i.e., TiO2). The composite high-entropy piezoelectric catalyst can be applied by external mechanical energy in the absence of light irradiation to undergo a redox reaction for the decomposition of wastewater or hydrogen generation.