Cu-Mn-O nano-particle/nano-sheet spinel-type materials as catalysts in methanol steam reforming (MSR) and preferential oxidation (PROX) reaction for purified hydrogen production

Nanocomposite Cu-Mn-O nano-particle (CuMnNP) and nano-sheet (CuMnNS) catalyst were successfully prepared using a one-step hydrothermal method in the absence of any templating reagent. Materials were characterised applying various structural techniques. SEM images showed that composite Cu -Mn oxide sheets were tailor-made synthesised by a one-pot urea-abetted protocol. Conversely, upon replacing carbamate by Na2CO3, oxidised metal Cu-Mn particles could be obtained. The formation of bulk mixed Cu-Mn phases resulted in an enhanced crystal lattice oxygen reactivity in CuMnNS. XPS, XRD and TPR measurements confirmed the presence of the Cu+ and Cu2+ species in nano-catalysts, and CuMnNS nanomaterials possessed more surface defects, thus causing a higher 0 2 adsorption/storage capacity. CuMnNS presented a superior catalytic activity as opposed to CuMnNP in the preferential oxidation (PROX) pathway of CO. With both CO2 and H2O in feed, a decrease in CO turnover was observed, due to a competitive interface binding of CO, CO2 and H2O. Compared to CuMnNP, CuMnNS also demonstrated a high time-on-stream conversion of methanol for the reforming for all operating conditions. (C) 2021 Elsevier Ltd. All rights reserved.

Automated summary

Nanocomposite Cu-Mn-O nano-particle (CuMnNP) and nano-sheet (CuMnNS) catalysts were successfully prepared via a one-step hydrothermal method without any templating reagent. CuMnNS showed enhanced crystal lattice oxygen reactivity and higher O2 adsorption/storage capacity compared to CuMnNP. Additionally, CuMnNS demonstrated superior catalytic activity in the preferential oxidation (PROX) pathway of CO.