Identification on catalytic sites of heterogeneous catalysts at atomic level is important to understand catalytic mechanism. Surface engineering on defects of metal oxides can construct new active sites and regulate catalytic activity and selectivity. Here we outline the strategy by controlling surface defects of nanoceria to create the solid frustrated Lewis pair (FLP) metal oxide for efficient hydrogenation of alkenes and alkynes. Porous nanorods of ceria (PN-CeO2) with a high concentration of surface defects construct new Lewis acidic sites by two adjacent surface Ce3+. The neighbouring surface lattice oxygen as Lewis base and constructed Lewis acid create solid FLP site due to the rigid lattice of ceria, which can easily dissociate H–H bond with low activation energy of 0.17 eV.

Effective activation of CO2 is a prerequisite for efficient utilization of CO2 in organic synthesis. Precisely controlling the interfacial events of solids shows potential for activation. Herein, defect-enriched CeO2 with constructed interfacial frustrated Lewis pairs (FLPs, two adjacent Ce3+···O2–) effectively activates CO2 via the interactions between C/Lewis basic lattice O2– and the two O atoms in CO2/two adjacent Lewis acidic Ce3+ ions. Selective cyclic carbonate production from a catalytically tandem protocol of olefins and CO2 is used to demonstrate FLP-inspired CO2 activation.

Introducing cerium (Ce) species into electrocatalysts has been recently developed as an effective approach to improve their oxygen evolution reaction (OER) performance. Importantly, the spatial distribution of Ce species in the hosts can determine the availability of Ce species either as additives or as co‐catalysts, which would dictate their different contributions to the enhanced electrocatalytic performance. Herein, the comprehensive investigations on two different catalyst configurations, namely CeO2‐embedded NiO (Ce‐NiO‐E) and CeO2‐surface‐loaded NiO (Ce‐NiO‐L), are performed to understand the effect of their specific spatial arrangements on OER characteristics. The Ce‐NiO‐E catalysts exhibit a smaller overpotential of 382 mV for 10 mA cm−2 and a lower Tafel slope of 118.7 mV dec−1, demonstrating the benefits of the embedded configuration for OER, as compared with those of Ce‐NiO‐L (426 mV and 131.6 mV dec−1) and pure NiO (467 mV and 140.7 mV dec−1), respectively. The improved OER property of Ce‐NiO‐E originates from embedding small‐sized CeO2 clusters into the host for the larger specific surface area, richer surface defects, higher oxygen adsorption capacity, and better optimized electronic structures of the surface active sites, as compared with Ce‐NiO‐L. Above findings provide a valuable guideline for and insight in designing catalysts with different spatial configurations for enhanced catalytic properties.

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Catalytic conversion of carbon dioxide (CO 2 ) into various highly value-added chemicals is an important challenge for the effective suppression of CO 2 emission and practical utilization of CO 2 . The search for a catalyst for the CO 2 conversion under mild conditions is a long-term target. Herein, we reported the as-received graphene oxides (GOs) alone as the efficient and green heterogeneous catalysts for the cycloaddition between epoxides and CO 2 at 1.0 atm. Asreceived GOs enabled the styrene oxide conversion of 97.8% with a 97.4% chemoselectivity to phenylethylene carbonate after 12 h of reaction. Kinetic and X-ray photoelectron spectroscopy analyses revealed that as-received GOs delivered a strong surface-depended catalytic performance, where the GO catalysts with the highest amount of the oxygen-containing groups exhibited the highest reaction rate. Control experiments indicated that the activation of CO 2 realized by DMF was independent of the CO 2 pressures. The activation of epoxide was achieved by the oxygen-containing groups in the GO catalysts as the surface active sites. The overall catalytic efficiency strongly depended on the surface properties of various GO catalysts for the cycloaddition reaction. Such unique carbon catalysts provide a cost-effective approach for CO 2 conversion under mild conditions.