Two-dimensional (2D) metal-organic framework (MOF) nanosheets are attracting increasing research interest. Here, for the first time, we report the facile synthesis of 2D porphyrin paddlewheel framework-3 (PPF-3) MOF nanosheets with thickness of ca. 12-43 nm. Through the simultaneous sulfidation and carbonization of PPF-3 MOF nanosheets, we have prepared the 2D nanocomposite of CoS1.097 nanoparticles (NPs) and nitrogen-doped carbon, referred to as CoSNC, in which the CoS1.097 NPs with size of ca. 10 nm are embedded in the nitrogen-doped carbon matrix. As a proof-of-concept application, the obtained 2D CoSNC nanocomposite is used as an electrode material for a supercapacitor, which exhibits a specific capacitance of 360.1 F g(-1) at a current density of 1.5 A g(-1). Moreover, the composite electrode also shows high rate capability. Its specific capacitance delivered at a current density of 30.0 A g(-1) retains 56.8% of the value at 1.5 A g(-1).

An optimized nanostructure design for high‐power, high‐energy lithium‐ion batteries and supercapacitors is realized by fabricating a nanocomposite with highly dispersed nanoparticles of active materials in a nanoporous carbon matrix. A nano‐LiFePO4/nanoporous carbon matrix nanocomposite forms a bridge between a supercapacitor and a battery electrode and offers a reasonable compromise between rate and capacity.

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The development of bifunctional electrocatalysts with high performance for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) with earth-abundant elements is still a challenge in electrochemical water splitting technology. Herein, we fabricated a free-standing electrocatalyst in the form of vertically oriented Fe-doped Ni3S2 nanosheet array grown on three-dimensional (3D) Ni foam (Fe-Ni3S2/NF), which presented a high activity and durability for both HER and OER in alkaline media. On the basis of systematic experiments and calculation, the Fe-doping was evidenced to increase the electrochemical surface area, improve the water adsorption ability, and optimize the hydrogen adsorption energy of Ni3S2, which resulted in the enhancement of HER activity on Fe-Ni3S2/NF. Moreover, metal sites of Fe-Ni3S2/NF were proved to play a significant role in the HER process. During the catalysis of OER, the formation of Ni–Fe (oxy)­hydroxide was observed on the near-surface section of Fe-Ni3S2/NF, and the introduction of the Fe element dramatically enhanced the OER activity of Ni3S2. The overall water splitting electrolyzer assembled by Fe-Ni3S2/NF exhibited a low cell voltage (1.54 V @ 10 mA cm–2) and a high durability in 1 M KOH. This work demonstrated a promising bifunctional electrocatalyst for water electrolysis in alkaline media with potential application in the future.

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A new facile solution method for the synthesis of high-quality CuInSe(2) nanocrystals with monodispersed size and uniform hexagonal shape was developed. A high-performance hybrid photodetector based on a hybrid film of CuInSe(2) nanocrystals and poly(3-hexylthiophene) was constructed. The device showed distinct "ON" and "OFF" states with a ratio of >100 in photocurrents responding to outside illumination. The high sensitivity and stability of the hybrid device revealed a broad prospect for use of the hybrid material in light detection and signal magnification for the development of large-area, low-cost, lightweight, and foldable products.

Indium-oxide (InO) nanobelts coated by a 5-nm-thick carbon layer provide an enhanced photocatalytic reduction of CO to CO and CH, yielding CO and CH evolution rates of 126.6 and 27.9 μmol h, respectively, with water as reductant and Pt as co-catalyst. The carbon coat promotes the absorption of visible light, improves the separation of photoinduced electron-hole pairs, increases the chemisorption of CO, makes more protons from water splitting participate in CO reduction, and thereby facilitates the photocatalytic reduction of CO to CO and CH.

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