Photocatalytic hydrogen evolution on a high-entropy oxide

Abstract

A two-phase high-entropy oxide with orange color and good light absorbance is introduced as a photocatalyst for hydrogen production.

High-entropy energy materials: challenges and new opportunities

“…18,67 The perovskite structure comprises at least two cation sublattices, both of which can be substituted and shared by multiple metals to form a variety of HECs. 43,[68][69][70][71][72] Other lattice structures, such as fluorite, 73-75 spinel 16,76,77 and layered oxides 13,55 were also identified and demonstrated their potential in various energy storage and conversion technologies (Fig. 2b).…”

“…Known procedures include electrocatalytic splitting by PtAuPdRhRu, 111 NiFeMoCoCr, 112 AlNiCuPtPdAu, 32 AlNiCuPtPdAuCoFe 32 and AlNiCuMoCoFe, 32 electrocatalytic splitting by FeCoNiAlTi high-entropy intermetallic (HEI), 113 CoCrFeMnNi-based high-entropy metal phosphide (HEMP) 25 and CoFeLaNiPt high-entropy metallic glass (HEMG), 38 thermochemical splitting by (FeMgCoNi)O x poly-cation oxide (PCO), 114 as well as photocatalytic splitting by TiZrHfNbTaO 11 HEO. 68 Liu et al 111 synthesized carbon-supported PtAuPdRhRu HEA nanoparticles via a facile ultrasonication-assisted wet-chemistry method, as shown in Fig. 5a.…”

Nano High‐Entropy Materials: Synthesis Strategies and Catalytic Applications

“…[45] A dual-phase perovskite, TiZrHfNbTaO 11 , including 60 mol% AB 2 O 7 monoclinic perovskite and 40 mol% of A 6 B 2 O 17 orthorhombic perovskite, was synthesized by mechanochemistry followed by high-pressure torsion method and high-temperature oxidation. [46] This two-phase oxide showed an appreciable light absorbance in the visible-light region with an appropriate valence and conduction bands for water splitting.…”

“…HEAs can be manufactured by physical mixing and mechanical alloying methods through ball milling of the metal powders with the process controlling agents. [ 18,25,43–46 ] A composite of HEA‐NPs and few‐layer graphene was first reported by Rekha et al via ball milling process following the graphene exfoliation. [ 47 ] The as‐synthesized NiCrCoCuFe HEA‐NPs showed a FCC structure and the composite exhibited excellent corrosion resistance.…”

“…[ 45 ] A dual‐phase perovskite, TiZrHfNbTaO 11 , including 60 mol% AB 2 O 7 monoclinic perovskite and 40 mol% of A 6 B 2 O 17 orthorhombic perovskite, was synthesized by mechanochemistry followed by high‐pressure torsion method and high‐temperature oxidation. [ 46 ] This two‐phase oxide showed an appreciable light absorbance in the visible‐light region with an appropriate valence and conduction bands for water splitting. Overall, the mechanical alloying method is a facile and scalable method for the HEMs preparation and there are no expensive precursors or harsh synthesis conditions such as high‐temperature involved.…”