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[Display omitted] • hs-CoFe catalyst with "plate reactor" structure was facilely synthesized. • Hetero-porous structure was constructed by selective etching and rGO supporting. • The OER/ORR was lowered to 0.608 V due to this smooth mass transfer channel. • ZAB performance and stability were significantly boosted. Large-scale application of zinc air batteries (ZABs) is impeded by the lack of efficient and cost-effective bifunctional oxygen catalysts. In this work, hetero-porous is rationally engineered for the carbon encapsulated CoFe catalyst, which is highly active toward both oxygen evolution reaction (OER) and oxygen evolution reaction (ORR). The hs-CoFe catalyst with "plate reactor" structure is facilely synthesized by combining the selective etching and reduced graphene oxide supporting to construct pores with size of 10–100 nm and 100–1000 nm, respectively, for smooth mass transfer. OER/ORR activities are significantly boosted, and difference between the potential to deliver 10 mA/cm2 OER and half wave potential of ORR is therefore lowered to 0.608 V while this potential difference of Pt/C-IrO 2 is 0.732 V. The corresponding ZAB exhibits a maximum power density of 232 mW/cm2, which sheds light on providing a novel strategy for oxygen reaction catalyst designation. [ABSTRACT FROM AUTHOR]

Highlights: [•] Two-bubble class model was employed for the gas–liquid mass transfer. [•] Axial dispersions of liquid and solid phases are incorporated in above model. [•] Bench-scale experiment was carried out in a 2L stainless steel tube of 2m long. [•] Scale-up simulations at a capacity of 1.0Mt/a for VR processing were conducted. [•] Due to the non-uniform distribution of catalyst, axial dispersion model is required. [ABSTRACT FROM AUTHOR]

• La modified Si pillared clays (SPC) with a house-of-cards structure were prepared. • S BET and V p values of Pt/LaSPC (0.5:1) was 544 m2/g and 1.33 cm3/g, respectively. • The particle size of PtO x was 3–5 nm for Pt/LaSPC (0.5:1) versus 5–7 nm for Pt/SPC. • The temperature of benzene combustion using 0.2% Pt/LaSPC (0.5:1) was about 200 °C. • 0.2% Pt/LaSPC (0.5:1) exhibited high stability at 195 °C in 100 h ongoing tests. La 2 O 3 modified silica-pillared clays (SPC) was synthesized by a soft template method. Both the basal spacing and the specific surface area increased after pillaring and modification, and the thermal stability was also improved, all of which could reduce the mass transfer resistance and improve the adsorption capacity of benzene. PtO x nanocrystalline catalysts were prepared by a high-temperature liquid reduction method. Among them, the catalyst with 0.2 wt% Pt loading and a La/KSF molar ratio of 0.5:1 (0.2% Pt/LaSPC (0.5:1)) showed the highest catalytic combustion activity and higher CO 2 selectivity, and the reaction temperature for benzene combustion was about 200 °C. Besides, the Pt0, Pt2+ and Pt4+ with particle sizes of about 3–5 nm coexisted on the surface of LaSPC (0.5:1). And this catalyst also exhibited good stability during the 100 h continuous reactions at 195 °C. The high dispersion of Pt particles, active oxygen species and strong redox property are responsible for the high activity of 0.2% Pt/LaSPC (0.5:1) for benzene combustion. [ABSTRACT FROM AUTHOR]