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Electroreduction of carbon dioxide into value-added fuels or chemicals using renewable energy helps to effectively reduce carbon dioxide emission and alleviate the greenhouse effect while storing intermittent energies. Due to the existing infrastructure of global natural gas utilization and distribution, methane produced in such a green route attracts wide interests. However, limited success has been witnessed in the practical application of catalysts imparting satisfactory methane activity and selectivity. Herein, we report the fabrication of an atomically dispersed Co−Cu alloy through the reconstruction of trace-Co doped Cu metal-organic framework. This catalyst exhibits a methane Faradaic efficiency of 60% ± 1% with the corresponding partial current density of 303 ± 5 mA·cm−2. Operando X-ray adsorption spectroscopy and attenuated-total-reflection surface enhanced infrared spectroscopy unravel that the introduction of atomically dispersed Co in Cu favors *CO protonation via enhancing surface water activation, and suppresses C−C coupling by reducing *CO coverage, thereby leading to high methane selectivity. [ABSTRACT FROM AUTHOR]

The slow kinetics at the cathode of oxygen reduction reaction (ORR) seriously limits the efficiencies of fuel cells and metal-air batteries. Pt, the state-of-the-art ORR electrocatalyst, suffers from high cost, low earth abundance, and poor stability. Here a self-templated strategy based on metal-organic frameworks (MOFs) is proposed for the fabrication of hollow nitrogen-doped carbon spheres that are embedded with cobalt nanoparticles (Co/HNC). The Co/HNC manifests better ORR activities, methanol tolerance, and stability than commercial Pt/C. The high ORR performance of Co/NHC can be attributed to the hollow structure which provides enlarged electrochemically active surface area, the formation of more Co-N species, and the introduction of defects. This work highlights the significance of rational engineering of MOFs for enhanced ORR activity and stability and offers new routes to the design and synthesis of high-performance electrocatalysts. [ABSTRACT FROM AUTHOR]

High-quality Pt-based catalysts are highly desirable for ethanol oxidation reaction (EOR), which is of critical importance for the commercial applications of direct ethanol fuel cells (DEFCs). However, most of the Pt-based catalysts have suffered from high cost and low operation durability. Herein a two-step method has been developed to synthesize porous Pt nanoframes decorated with Bi(OH)3, which show excellent catalytic activity and operation durability in both alkaline and acidic media. For example, the nanoframes show a mass activity of 6.87 A·mgPt−1 in alkaline media, which is 13.5-fold higher than that of commercial Pt/C. More importantly, the catalyst can be reactivated simply, which shows negligible activity loss after running for 180,000 s. Further in situ attenuated total reflection-infrared (ATR-IR) absorption spectroscopy and CO-stripping experiments indicate that surface Bi(OH)3 species can greatly facilitate the formation of adsorbed OH species and subsequently remove carbonaceous poison, resulting in a significantly enhanced stability towards EOR. This work may favor the tailoring of desired electrocatalysts with high activity and durability for future commercial application of DEFCs. [ABSTRACT FROM AUTHOR]