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Zinc-air batteries are regarded as a promising candidate for next-generation clean and sustainable energy storage devices, due to their low-cost, safety, eco-friendliness, and high specific energy density. In zinc-air batteries,...

Platinum is the most efficient catalyst for hydrogen evolution reaction in acidic conditions, but its widespread use has been impeded by scarcity and high cost. Herein, Pt atomic clusters (Pt ACs) containing Pt-O-Pt units were prepared using Co/N co-doped carbon (CoNC) as support. Pt ACs are anchored to single Co atoms on CoNC by forming strong interactions. Pt-ACs/CoNC exhibits only 24 mV overpotential at 10 mA cm−2 and a high mass activity of 28.6 A mg−1 at 50 mV, which is more than 6 times higher than commercial Pt/C with any Pt loadings. Spectroscopic measurements and computational modeling reveal the enhanced hydrogen generation activity attributes to the charge redistribution between Pt and O atoms in Pt-O-Pt units, making Pt atoms the main active sites and O linkers the assistants, thus optimizing the proton adsorption and hydrogen desorption. This work opens an avenue to fabricate noble-metal-based ACs stabilized by single-atom catalysts with desired properties for electrocatalysis.

A considerable amount of platinum (Pt) is required to ensure an adequate rate for the oxygen reduction reaction (ORR) in fuel cells and metal‐air batteries. Thus, the implementation of atomic Pt catalysts holds promise for minimizing the Pt content. In this contribution, atomic Pt sites with nitrogen (N) and phosphorus (P) co‐coordination on a carbon matrix (PtNPC) are conceptually predicted and experimentally developed to alter the d‐band center of Pt, thereby promoting the intrinsic ORR activity. PtNPC with a record‐low Pt content (≈0.026 wt %) consequently shows a benchmark‐comparable activity for ORR with an onset of 1.0 VRHE and half‐wave potential of 0.85 VRHE. It also features a high stability in 15 000‐cycle tests and a superior turnover frequency of 6.80 s−1 at 0.9 VRHE. Damjanovic kinetics analysis reveals a tuned ORR kinetics of PtNPC from a mixed 2/4‐electron to a predominately 4‐electron route. It is discovered that coordinated P species significantly shifts d‐band center of Pt atoms, accounting for the exceptional performance of PtNPC.

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Highly porous boron nitride (BN) composed of a flexible network of hexagonal BN nanosheets was synthesized via thermal treatment of a boric acid/urea mixture. The as-prepared sponge-like BN displayed fast adsorption rates and ultrahigh adsorption capacities for gaseous formaldehyde (HCHO), e.g., 19 mg/g in equilibrium with approximately 20 ppm of HCHO in air, which is an order of magnitude higher than those of other tested materials, including commercial hexagonal BN and various metal oxides. The superb HCHO adsorption performance of the porous BN is mainly due to its large specific surface area (627 m 2 /g), as well as the abundant surface hydroxyl and amine groups. Moreover, chemisorption can occur on the BN layers and contribute to the high HCHO uptake capacity via Cannizzaro-type disproportionation reactions, during which HCHO is transformed into less toxic formic acid and methanol. This porous BN is a promising adsorbent for indoor HCHO removal and may serve as the support for highly efficient HCHO decomposition catalysts.

The increasing interest in fuel cell technology encourages the development of efficient and low‐cost electrocatalysts to replace the Pt based materials for catalyzing the cathodic oxygen reduction reaction (ORR). In the present work, a nitrogen and phosphorus co‐coordinated manganese atom embedded mesoporous carbon composite (MnNPC‐900) is successfully prepared via a polymerization of o‐phenylenediamine followed by calcination at 900 °C. The MnNPC‐900 composite shows a high ORR activity in alkaline media, offering an onset potential of 0.97 V, and a half‐wave potential of 0.84 V (both vs reversible hydrogen electrode) with a loading of 0.4 mg cm−2. This performance not only exceeds its phosphorus‐free counterpart (MnNC‐900), but also is comparable to the Pt/C catalyst under identical measuring conditions. The significantly enhanced ORR performance of MnNPC‐900 can be ascribed to: i) the introduction of phosphorus assists the generation of mesopores during the pyrolysis and endows the MnNPC‐900 composite with large surface area and pore volume, thus facilitating the mass transfer process and increases the number of exposed active sites. ii) The formation of N,P co‐coordinated atomic‐scale Mn sites (MnNxPy), which modifies the electronic configuration of the Mn atoms and thereby boosts the ORR catalytic activity.