Recently, metal‐free, heteroatom‐doped carbon nanomaterials have emerged as promising electrocatalysts for the oxygen evolution reaction (OER), but their synthesis is a tedious process involving energy‐wasting calcination. Molecular electrocatalysts offer attractive catalysts for the OER. Here, phytic acid (PA) was selected to investigate the OER activity of carbons in organic molecules by DFT calculations and experiments. Positively charged carbons on PA were very active towards the OER. The PA molecules were fixed into a porous, conductive hydrogel with a superhydrophilic surface. This outperformed most metal‐free electrocatalysts. Besides the active sites on PA, the high OER activity was also related to the porous and conductive networks on the hydrogel, which allowed fast charge and mass transport during the OER. Therefore, this work provides a metal‐free, organic‐molecule‐based electrocatalyst to replace carbon nanomaterials for efficient OER.

A facile route to scalable production of N and S co‐doped, hierarchically porous carbon nanofiber (NSHCF) membranes (ca. 400 cm2 membrane in a single process) is reported. As‐synthesized NSHCF membranes are flexible and free‐standing, allowing their direct use as cathodes for efficient electrochemical CO2 reduction reaction (CO2RR). Notably, CO with 94 % Faradaic efficiency and −103 mA cm−2 current density are readily achieved with only about 1.2 mg catalyst loading, which are among the best results ever obtained by metal‐free CO2RR catalysts. On the basis of control experiments and DFT calculations, such outstanding CO Faradaic efficiency can be attributed to the co‐doped pyridinic N and carbon‐bonded S atoms, which effectively decrease the Gibbs free energy of key *COOH intermediate. Furthermore, hierarchically porous structures of NSHCF membranes impart a much higher density of accessible active sites for CO2RR, leading to the ultra‐high current density.

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involved half reactions, including oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) for water splitting systems, and OER and oxygen reduction reaction (ORR) for metal-air batteries. [3] In this context, robust electrocatalysts are required to boost these half reactions for achieving large current densities at small overpotentials. Though noble metal-based electrocatalysts have shown satisfying activity for OER, HER, or ORR, it is still challenging to explore one single noble metal-constructed electrocatalysts possessing high activity toward all above three reactions, which therefore complicates the manufactures and operation of devices. [4] For example, in a water splitting system, RuO 2 and IrO 2 are benchmark electrocatalysts for OER; however, their HER activity is poor. In case of metal-air batteries, Pt/C holds the nearly highest activity for ORR, whereas it is not very active for OER. Moreover, above noble metals-based electrocatalysts suffer from poor stability, high cost, and low abundance. [5] Therefore, in terms of industrial application and cost saving, it is extremely appealing to develop noble metal-free and trifunctional electrocatalysts that combine high activity and excellent stability for both OER, HER, and ORR to achieve high efficiency on the water splitting and metal-air batteries.Recently, metal-free N-doped carbon nanomaterials have emerged as promising substitutes for precious metals to reduce the cost and improve the stability of OER, HER, or ORR electrocatalysts. [6] Rational doping a second heteroatoms (B, S, and P) into N-doped carbon nanomaterials is an effective route for optimizing their electronic and chemical features to further enhance the electrocatalytic activity. [7] For instance, the N, P-codoped carbon networks displayed excellent activity for both ORR and HER. [8] However, up to now, the performance of dual N, O-codoped carbon nanomaterials for OER, ORR, or HER is rarely reported. On the other hand, inadequate mass transport could ineluctably reduce the electrocatalytic performance especially at large current densities, during which large amount of gas are required to transport or consume for OER, HER, and ORR. Although the rotating disk electrode (RDE) could Despite the exciting achievements made in synthesis of monofunctional electrocatalysts for oxygen reduction reaction (ORR), oxygen evolution reaction (OER), or hydrogen evolution reaction (HER), it is challenging to develop trifunctional electrocatalysts for both ORR/OER/HER. Herein, N, O-codoped graphene nanorings-integrated boxes (denoted NOGB) are crafted via high-temperature pyrolysis and following acid etching of hybrid precursors containing polymers and Prussian blue analogue cubes. The electrochemical results signified that the resulting NOGB-800 (800 refers to pyrolysis temperature) is highly active for trifunctional electrocatalysis of ORR/OER/HER. This can be reasonably attributed to the advanced nanostructures (i.e., the hierarchically porous nanostructures on the hollow nanorings) and...

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