Multi-component nanoporous alloy/(oxy)hydroxide for bifunctional oxygen electrocatalysis and rechargeable Zn-air batteries

High-entropy materials for catalysis: A new frontier

“…In comparison, the phase-segregated multimetallic catalysts synthesized using the wet impregnation approach suffered from severe oxidative degradation. Fang et al ( 94 ) integrated the noble metal–free HEAs in aqueous Zn-air batteries and demonstrated the as-formed multicomponent surface oxides with favorable e g occupancy and optimal covalency of the metal-oxygen bond impart the enhanced electrochemical activity and stability.…”

High-entropy energy materials: challenges and new opportunities

“…For instance, the large lattice strain in the HEAs is beneficial to the absorption of hydrogen in both octahedral and tetrahedral sites, providing great potential for hydrogen energy applications. 10,[28][29][30] Sluggish diffusion effects lead the alloys to develop nanocrystalline or even amorphous structures, which is promising for electrocatalysis, including methanol oxidation 31,35,62,63 or oxygen evolution 39,41,44,46,47 and reduction. 31,52,64 Overall, HEAs can be regarded as atomicscale composites, since multiprinciple metals are incorporated and the interactions among the different elements are playing an important role, 8,27,59 resulting in a kind of composite (cocktail) effect on properties.…”

“…Some noble-metal-free HEAs, such as FeNiMnCrCu, 44 FeCoNiCrAl, 44 CoCrFeMnNi, 47 FeCoNiMn 37 and AlCoNiFeX (X = Nb, Mo, Cr), 41,46 were studied in an alkaline environment, showing great potential for future applications as OER electrocatalysts. Qiu et al 41 synthesized several nanoporous AlCoNiFeX (X = Nb, Mo, Cr, V, Zr, Mn, Cu)-based HEAs that have a high-entropy (oxy)hydroxide surface.…”

“…6c and d). Furthermore, this group assembled both aqueous and solid-state zinc-air battery cells with AlCoNiFeCrmodified carbon cloth as cathode and a Zn foil anode, 46 showing superior performance compared to Pt/C-IrO 2 -based battery cells. Similarly, a core-shell structure of FeCoNiMnbased HEA was investigated by Dai et al 37 Through a CV scan activation, MO x (M = Fe, Co, Ni, Mn) nanosheets were grown directly onto the FeCoNiMn particle surface, thereby forming the core-shell structure.…”

“…Note that lattice distortions are commonly developing in highentropy alloys (HEAs) 5,8,9,26,27 and are supportive to gas absorption due to the formation of more suitable reaction sites, leading to promising properties, especially for hydrogen storage. 10,[28][29][30] The strong synergistic effects among the functional units are beneficial to the catalysis of energy conversion processes, boosting the investigation of high-entropy noblemetal and noble-metal-free electrocatalysts in methanol oxidation [31][32][33][34][35][36] as well as oxygen evolution 25,[37][38][39][40][41][42][43][44][45][46][47] and reduction. 31,32,45,46,[48][49][50][51][52] In the battery field, HEMs also exhibit attractive properties.…”