Efficient and earth‐abundant materials with multifunctional electrocatalytic properties within a wide range of pH are the new darlings for developing green energy conversion and storage techniques. A novel porous covalent phenanthroline framework (Fe‐Phen‐COFs) that involved Fe‐DMSO (dimethyl sulfoxide) coordination complexes is successfully synthesized using 3, 8‐dibromophenanthroline and 1, 3, 5‐benzenetriboronicacid trivalent alcohol ester as a rigid building block via Suzuki coupling reaction. Fe‐Phen‐COFs as the self‐carrier enriched with Fe, S, N, and C is pyrolyzed to produce N‐S‐codoping carbons with embedded core–shell Fe3C and FeS composite nanostructures (FeS/Fe3C@N‐S‐C). The FeS/Fe3C@N‐S‐C‐800 obtained by pyrolysis at 800 °C exhibits efficient trifunctional electrocatalytic activity for oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER) within a wide pH range. Impressively, the ORR half‐potential of FeS/Fe3C@N‐S‐C‐800 reaches 0.87 V in 0.1 m KOH, more positive than the previously reported Pt‐free electrocatalysts. It could be utilized as the advanced air electrode materials in zinc–air batteries, which exhibit an excellent power density and cycling stability superior to those of Pt/C‐based zinc–air battery. Thermal conversion of novel Fe‐Phen‐COFs provides an effective strategy to prepare high‐performance trifunctional electrocatalytic materials for the new‐generation powerful energy conversion technologies.

A new porous covalent porphyrin framework (CPF) filled with triphenylphosphine was designed and synthesized using the rigid tetrakis(p-bromophenyl)porphyrin (TBPP) and 1,3,5-benzenetriboronic acid trivalent alcohol ester as building blocks. The carbonization of this special CPF has afforded coupled FeP and FeN nanoparticles embedded in N-doped carbons (FeP/FeN@N-doped carbons). This CPF serves as an "all in one" precursor of Fe, N, P, and C. The porous property and solid skeleton of the CPF endow FeP/FeN@N-doped carbons with porous structure and a high degree of graphitization. As a result, FeP/FeN@N-doped carbons exhibited highly efficient multifunctional electrocatalytic performance for water splitting and oxygen electroreduction. Typically, FeP/FeN@C-800, obtained at a heat-treatment temperature of 800 °C, showed an ORR half-wave potential of 0.80 V in alkaline media and 0.68 V in acidic media, close to that of commercial Pt/C catalysts. FeP/FeN@C-800 also displayed efficient OER and HER activities, comparable to other phosphide and nitride electrocatalysts. The coupled FeN and FeP nanoparticles embedded in carbons exert unique catalytic efficiency for water splitting and fuel cells.

serves on speakers bureaus for Gilead Sciences and Teva; S.S.M. was an employee of Gilead Sciences and is an equity holder of Gilead Sciences and Five Prime Therapeutics; P.B. is an employee of and has stock holdings in Gilead Sciences, holds a leadership role on the board of directors for Tioma Therapeutics, consults for Dicerna Pharmaceuticals, and has intellectual property interests with Sanofi and AVEO Pharmaceuticals; P.C.Y., R.H., X.H., and J.J. are employees and stockholders of Gilead Sciences; C.D.F. declares no competing financial interests. Z.Z. was an employee of Gilead Sciences.

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Electrocatalytic water splitting for the production of hydrogen proves to be effective and available. In general, the thermal radiation synthesis usually involves a slow heating and cooling process. Here, a high‐frequency induction heating (IH) is employed to rapidly prepare various self‐supported electrocatalysts grown on Ni foam (NF) in liquid‐ and gas‐phase within 1–3 min. The NF not only serves as an in situ heating medium, but also as a growth substrate. The as‐synthesized Ni nanoparticles anchored on MoO2 nanowires supported on NF (Ni‐MoO2/NF‐IH) enable catalysis of hydrogen evolution reaction (HER), showing a low overpotential of −39 mV (10 mA cm−2) and maintaining the stability of 12 h in alkaline condition. Moreover, the NiFe layered double hydroxide (NiFe LDH/NF‐IH) is also synthesized via IH and affords outstanding oxygen evolution reaction (OER) activity with an overpotential of 246 mV (10 mA cm−2). The Ni‐MoO2/NF‐IH and NiFe LDH/NF‐IH are assembled to construct a two‐electrode system, where a small cell voltage of ≈1.50 V enables a current density of 10 mA cm−2. More importantly, this IH method is also available to rapidly synthesize other freestanding electrocatalysts on NF, such as transition metal hydroxides and metal nitrides.

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SummaryThe large-scale application of economically efficient electrocatalysts for hydrogen evolution reaction (HER) is limited in view of the high cost of polymer binders (Nafion) for immobilizing of powder catalysts. In this work, nitrogen-doped molybdenum carbide nanobelts (N-Mo2C NBs) with porous structure are synthesized through a direct pyrolysis process using the pre-prepared molybdenum oxide nanobelts (MoO3 NBs). Nanocellulose instead of Nafion-bonded N-Mo2C NBs (N-Mo2C@NCs) exhibits superior performance toward HER, because of excellent dispersibility and multiple exposed catalytically active sites. Furthermore, the conductive film composed of N-Mo2C NBs, graphene nanosheets, and nanocellulose (N-Mo2C/G@NCs) is fabricated by simple vacuum filtration, as flexible and editable electrode, which possesses excellent performance for scale HER applications. This work not only proposes the potential of nanocellulose to replace Nafion for binding powder catalysts, but also offers a facile strategy to prepare flexible and conductive films for a wide variety of nanomaterials.