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A COOH-terminated nitrogen-doped carbon aerogel exhibited 100% selectivity to two-electron oxygen reduction, exceeding reported carbonaceous and noble metal catalysts.

NOx− reduction acts a pivotal part in sustaining globally balanced nitrogen cycle and restoring ecological environment, ammonia (NH3) is an excellent energy carrier and the most valuable product among all the products of NOx− reduction reaction, the selectivity of which is far from satisfaction due to the intrinsic complexity of multiple‐electron NOx−‐to‐NH3 process. Here, we utilize the Schottky barrier‐induced surface electric field, by the construction of high density of electron‐deficient Ni nanoparticles inside nitrogen‐rich carbons, to facilitate the enrichment and fixation of all NOx− anions on the electrode surface, including NO3− and NO2−, and thus ensure the final selectivity to NH3. Both theoretical and experimental results demonstrate that NOx− anions were continuously captured by the electrode with largely enhanced surface electric field, providing excellent Faradaic efficiency of 99 % from both electrocatalytic NO3− and NO2− reduction. Remarkably, the NH3 yield rate could reach the maximum of 25.1 mg h−1 cm−2 in electrocatalytic NO2− reduction reaction, outperforming the maximum in the literature by a factor of 6.3 in neutral solution. With the universality of our electrocatalyst, all sorts of available electrolytes containing NOx− pollutants, including seawater or wastewater, could be directly used for ammonia production in potential through sustainable electrochemical technology.

Interface engineering is an efficient strategy for passivating defects, improving carrier dynamics, suppressing ion migration, and enhancing the performance of perovskite photovoltaic cells.

Platinum (Pt) is the most effective bench-marked catalyst for producing renewable and clean hydrogen energy by electrochemical water splitting. There is demand for high HER catalytic activity to achieve efficient utilization and minimize the loading of Pt in catalysts. In this work, we significantly boost the HER mass activity of Pt nanoparticles in Pt x /Co to 8.3 times higher than that of commercial Pt/C by using Co/NC heterojunctions as a heterogeneous version of electron donors. The highly coupled interfaces between Co/NC and Pt metal enrich the electron density of Pt nanoparticles to facilitate the adsorption of H + , the dissociation of Pt À H bonds and H 2 release, giving the lowest HER overpotential of 6.9 mV vs. RHE at 10 mA cm À2 in acid among reported HER electrocatalysts. Given the easy scale-up synthesis due to the stabilization of ultrafine Pt nanoparticles by Co/NC solid ligands, Pt x /Co can even be a promising substitute for commercial Pt/C for practical applications.

As a new type of heterogeneous catalyst with “homogeneous‐like” activity, single‐site transition‐metal materials are usually treated as integrated but separate active centers. A novel grouping effect is reported for single Ni−N4 sites in nitrogen‐doped carbon (Ni/NC), where an effective ligand‐stabilized polycondensation method endows Ni/NC nanocatalysts with a high content of single‐site Ni up to 9.5 wt %. The enhanced electron density at each single Ni−N4 site promotes a highly efficient hydrogen transfer, which is exemplified by the coupling of benzyl alcohol and aniline into N‐benzylaniline with a turnover frequency (TOF) value of 7.0 molN‐benzylaniline molmetal−1 h−1; this TOF outpaces that of reported stable non‐noble‐metal‐based catalysts by a factor of 2.

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