Recently, the emergence of conductive metal-organic frameworks (MOFs) has given great prospects for their applications as active materials in electronic devices. In this work, a high-quality, free-standing conductive MOF membrane was prepared by an air-liquid interfacial growth method. Accordingly, field-effect transistors (FETs) possessing a crystalline microporous MOF channel layer were successfully fabricated for the first time. The porous FETs exhibited p-type behavior, distinguishable on/off ratios, and excellent field-effect hole mobilities as high as 48.6 cm V s, which is even comparable to the highest value reported for solution-processed organic or inorganic FETs.

Lithium–sulfur (Li–S) batteries are appealing candidates for next‐generation high‐energy rechargeable batteries, but practical applications are still limited by poor cyclic life, which is caused by severe polysulfide shuttling in high‐sulfur‐loading batteries. Herein, a facile route is presented to fabricate high‐performance Li–S batteries using a crystalline microporous membrane, which is prepared using a conductive metal–organic framework (MOF) material. With ordered microporous structure, large specific surface area, good sulphiphilicity, and excellent conductivity, the MOF membrane is grown in situ on the commercial separator and is an ideal light‐weight barrier (0.066 mg cm−2) for suppressing the polysulfide shuttling, which can significantly promote the capacities, rate capabilities, and cycling stabilities of Li–S batteries. Taking the advantage of this functional separator, the high‐sulfur‐loading Li–S battery (8.0 mg cm−2 and 70 wt% of sulfur in cathode) delivers a high area capacity of 7.24 mAh cm−2 after 200 cycles, thus providing a promising path toward advanced Li–S batteries.

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Anchoring Cu into a prefabricated COF structure yielded a high-performance photocatalytic hydrogen evolution catalyst.

Acidic oxygen reduction is vital for renewable energy devices such as fuel cells. However, many aspects of the catalytic process are still uncertain—especially the large difference in activity in acidic and alkaline media. Thus, the design and synthesis of model catalysts to determine the active centers and the inactivation mechanism are urgently needed. We report a pyrolysis‐free synthesis route to fabricate a catalyst (CPF‐Fe@NG) for oxygen reduction in acidic conditions. By introducing a deprotonation process, we extended the oxygen reduction reaction (ORR) activity from alkaline to acidic conditions. CPF‐Fe@NG demonstrated outstanding performance with a half‐wave potential of 853 mV (vs. RHE) and good stability after 10000 cycles in 1 M HClO4. The pyrolysis‐free route could also be used to assemble fuel cells, with a maximum power density of 126 mW cm−2. Our findings offer new insights into the ORR process to optimize catalysts for both mechanistic studies and practical applications.

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Catalysts capable of electrochemical overall water splitting in acidic, neutral, and alkaline solution are important materials. This work develops bifunctional catalysts with single atom active sites through a pyrolysis-free route. Starting with a conjugated framework containing Fe sites, the addition of Ni atoms is used to weaken the adsorption of electrochemically generated intermediates, thus leading to more optimized energy level sand enhanced catalytic performance. The pyrolysis-free synthesis also ensured the formation of well-defined active sites within the framework structure, providing ideal platforms to understand the catalytic processes. The as-prepared catalyst exhibits efficient catalytic capability for electrochemical water splitting in both acidic and alkaline electrolytes. At a current density of 10 mA cm−2, the overpotential for hydrogen evolution and oxygen evolution is 23/201 mV and 42/194 mV in 0.5 M H2SO4 and 1 M KOH, respectively. Our work not only develops a route towards efficient catalysts applicable across a wide range of pH values, it also provides a successful showcase of a model catalyst for in-depth mechanistic insight into electrochemical water splitting.

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