Herein, in situ generation of CuCoNi nanoalloys over a high-entropy oxide Co 3 MnNiCuZnO x matrix has been employed to generate a sintering-resistant metal-oxide interface for the CO 2 hydrogenation reaction. The high-entropy Co 3 MnNiCuZnO x catalyst with a single reverse spinel structure was synthesized by a mechanochemical redox-based process and thermal treatment just at 600 °C. Interestingly, the entropy-driven force allows the exsolution and dissolution of CuCoNi alloys under reductive and oxidative recyles, which results in the dynamics confinement of the supported metals. With high temperature (500 °C) CO 2 hydrogenation as a model reaction, the restriction of CuCoNi nanoparticles over a high-entropy Co 3 MnNiCuZnO x matrix guaranteed long-term thermal stability (>100 h). In comparison, binary CoMnO x as a control catalyst deactivated in 10 h. This high-entropy stabilization may inspire a number of sintering-resistant catalysts in the near future.

Doped Ceria with abundant oxygen vacancies exhibits enhanced performance in heterogeneous oxidation. In principle, doping 50 mol% divalent cations (such as: Cu2+, Zn2+, and Mg2+) into CeO2 lattice would produce an exceptional catalyst with maximum active oxygen species. However, the huge size gap between Ce (IV) and divalent metal cations obstructs its synthesis. Here, we utilize the theory of increasing configurational entropy with five metal dopants to lower the Gibbs‐free energy, and successfully incorporate 50 mol% divalent metal cations into CeO2 lattice. This unique doping environment endows Ce0.5Zn0.1Co0.1Mg0.1Ni0.1Cu0.1Ox two features: (a) Abundant active oxygen species for excellent performance in volatile organic compounds catalytic oxidation; (b) Bring multi reactive sites, which enable the simultaneous combustion of carbon monoxide, propylene and toluene. Moreover, the increased entropy value makes Ce0.5Zn0.1Co0.1Mg0.1Ni0.1Cu0.1Ox an ultra‐stable catalyst in both thermal and hydrothermal conditions (e.g., Working >200 hr in water‐resistance experiment).

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A mechanochemical redox reaction between KMnO4 and CoCl2 was developed to obtain a CoxMn1-xOy catalyst with a specific surface area of 479 m 2 g -1 , which was higher than that obtained using a co-precipitation (CP) method (34 m 2 g -1 ), sol-gel (SG) method (72 m 2 g -1 ), or solution redox process (131 m 2 g -1 ). During catalytic combustion, this CoxMn1-xOy catalyst exhibited better activity (T100 for propylene = ~200 °C) than the control catalysts obtained using the SG (325 °C) or CP (450 °C) methods. The mechanical action, mainly in the form of kinetic energy and frictional heating, may generate a high degree of interstitial porosity, while the redox reaction could contribute to good dispersion of cobalt and manganese species. Moreover, the as-prepared CoxMn1-xOy catalyst worked well in the presence of water vapor (H2O 4.2%, >60 h) or SO2 (100 ppm) and at high temperature (400 °C, > 60 h). The structure MnO2•(CoOOH)2.93 was suggested for the current CoxMn1-xOy catalyst. This catalyst could be extended to the total oxidation of other typical hydrocarbons (T90 = 150 °C for ethanol, T90 = 225 °C for acetone, T90 = 250 °C for toluene, T90 = 120 °C for CO, and T90 = 540 °C for CH4). Scale-up of the synthesis of CoxMn1-xOy catalyst (1 kg) can be achieved via ball milling, which may provide a potential strategy for real world catalysis.

The sintering of Supported Transition Metal Catalysts (STMCs) is a core issue during high temperature catalysis. Perovskite oxides as host matrix for STMCs are proven to be sintering-resistance, leading to a family of self-regenerative materials. However, none other design principles for self-regenerative catalysts were put forward since 2002, which cannot satisfy diverse catalytic processes. Herein, inspired by the principle of high entropy-stabilized structure, a concept whether entropy driving force could promote the self-regeneration process is proposed. To verify it, a high entropy cubic Zr0.5(NiFeCuMnCo)0.5Ox is constructed as a host model, and interestingly in situ reversible exsolution-dissolution of supported metallic species are observed in multi redox cycles. Notably, in situ exsolved transition metals from high entropy Zr0.5(NiFeCuMnCo)0.5Ox support, whose entropic contribution (TΔSconfig = T⋆12.7 J mol−1 K−1) is predominant in ∆G, affording ultrahigh thermal stability in long-term CO2 hydrogenation (400 °C, >500 h). Current theory may inspire more STWCs with excellent sintering-resistance performance.