Quinary metal oxide NiCoMnCeCaOx nanorod as a multifunctional catalyst towards hydrogen production from ethanol steam reforming: Synergistic effect of polymetallic component

Ethanol has been recognized as a preferred hydrogen carrier, while coke deposition is a crucial issue during the typical ethanol steam reforming (ESR) process for hydrogen production, which hinders the catalytic stability. Polymetallic catalyst is a type of promising candidate catalyst owing to its adjustable catalytic performance, whereas its catalytic mechanism has rarely been investigated in detail. In this work, a nanorod-type quinary metal oxide NiCoMnCeCaO x was tactfully designed and synthesized. In the synthesized catalyst, transition metals (Ni, Co) were employed as active components for C-C and C-H bond cracking; oxygen carrier species (Mn, Ce) were exploited to improve the oxygen release capacity and lattice oxygen mobility; and alkali metals (Ca) were designed to enhance H 2 O absorption and CO 2 capture. It was interesting that surface reconstruction was discovered for NiCoMnCeCaO x during the initial stage of ESR, NiCo nanoalloy was self-assembly generated to form a supported-like NiCo/NiCoMnCeCaO x structure, accompanied with the gradually increased H 2 production efficiency and stable at 120.5 μmol/s with 99.92 % ethanol conversion after 20th min. The synergistic effect of the polymetallic component and the specific morphological structure of NiCoMnCeCaO x contributed to its outstanding carbon tolerance performance. It achieved efficient H 2 production through ethanol dehydration and subsequent deep dehydrogenation. The new composite material (MWCNT@NiCoMnCeCaO x ) induced by ESR reaction exhibited specific electrochemical performance. This work attempted to offer certain references for the design of multifunctional catalysts for H 2 production.