Crystalline and porous covalent organic frameworks (COFs) and metal-organic frameworks (MOFs) materials have attracted enormous attention in the field of photocatalytic H evolution due to their long-range order structures, large surface areas, outstanding visible light absorbance, and tunable band gaps. In this work, we successfully integrated two-dimensional (2D) COF with stable MOF. By covalently anchoring NH -UiO-66 onto the surface of TpPa-1-COF, a new type of MOF/COF hybrid materials with high surface area, porous framework, and high crystallinity was synthesized. The resulting hierarchical porous hybrid materials show efficient photocatalytic H evolution under visible light irradiation. Especially, NH -UiO-66/TpPa-1-COF (4:6) exhibits the maximum photocatalytic H evolution rate of 23.41 mmol g h (with the TOF of 402.36 h ), which is approximately 20 times higher than that of the parent TpPa-1-COF and the best performance photocatalyst for H evolution among various MOF- and COF-based photocatalysts.

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The design of highly stable, selective and efficient electrocatalysts for CO2 reduction reaction is desirable while largely unmet. In this work, a series of precisely designed polyoxometalate-metalloporphyrin organic frameworks are developed. Noted that the integration of {ε-PMo8VMo4VIO40Zn4} cluster and metalloporphyrin endows these polyoxometalate-metalloporphyrin organic frameworks greatly advantages in terms of electron collecting and donating, electron migration and electrocatalytic active component in the CO2 reduction reaction. Thus-obtained catalysts finally present excellent performances and the mechanisms of catalysis processes are discussed and revealed by density functional theory calculations. Most importantly, Co-PMOF exhibits remarkable faradaic efficiency ( > 94%) over a wide potential range (−0.8 to −1.0 V). Its best faradaic efficiency can reach up to 99% (highest in reported metal-organic frameworks) and it exhibits a high turnover frequency of 1656 h−1 and excellent catalysis stability ( > 36 h).

Metal-organic frameworks (MOFs) with high porosity could act as an ideal substitute for supercapacitors, but their poor electrical conductivities limit their electrochemical performances. In order to overcome this problem, conductive polypyrrole (PPy) has been introduced and a novel nanocomposite resulting from polyoxometalate (POM)-based MOFs (NENU-5) and PPy has been reported. It comprises the merits of POMs, MOFs, and PPy. Finally, the highly conductive PPy covering the surfaces of NENU-5 nanocrystallines can effectively improve the electron/ion transfer among NENU-5 nanocrystallines. The optimized NENU-5/PPy nanocomposite (the volume of Py is 0.15 mL) exhibits high specific capacitance (5147 mF·cm), larger than that of pristine NENU-5 (432 mF·cm). Furthermore, a symmetric supercapacitor device based on a NENU-5/PPy-0.15 nanocomposite possesses an excellent areal capacitance of 1879 mF·cm, which is far above other MOF-based supercapacitors.

cells. [3] Up to now, Pt-based electrocatalysts have been extensively considered to be the most active ORR electrocatalysts in electrochemical cell reactions. [4][5][6] Nevertheless, crustal rarity, high cost, poor stability, and methanol crossover of Ptbased materials and the sluggish kinetics of cathodic reaction greatly restrict their large-scale practical application. In this connection, a great deal of investigation has been performed based on the study of efficient non-noble metal catalysts, which mainly consists of non-noble metal compounds (e.g., oxides, nitrides, phosphide, and chalcogenides), metal-free catalysts as well as carbonitrides. [7][8][9][10][11] Then, the transition metal carbonitrides (TM-N-C, where TM represents mainly Co, Fe), obtained by carbonization various nitrogen-rich precursor (such as dicyandiamide, melamine, polyaniline, and metal-organic frameworks (MOFs)), have been widely explored to substitute precious metal catalysts because of their high catalytic activity and durability in acid or alkaline electrolyte. [12][13][14][15] In recent years, MOFs have been served as precursors to fabricate the functional nanostructured porous carbon-based electrocatalysts, which gives the credit to their excellent intrinsic characteristics, such as large specific surface area derived from the porosity and the diversity of structure and function stemmed from different metal ions and organic ligands. [16][17][18][19][20][21][22] In particular, Zn-Co bimetallic ZIFs (BMZIFs (ZIF-67 and ZIF-8)) have been extensively employed as precursors to develop efficient Co-based porous nitrogen-doped carbon catalysts, [22][23][24] which attributes to their unique merits. I) Co-N x sites can be easily produced by pyrolysis due to Co metal directly connected to N species. [25,26] II) The larger surface area derived from the pore structure, due to the evaporation of Zn at high temperature. [27,28] III) Uniform N atoms doped into the obtained carbon skeleton after calcination of Zn-ZIF. [29] However, the skeleton of MOFs was generally prone to collapse and aggregate in the pyrolysis process (>700 °C), [17,30] resulting in fewer pore structures, which greatly reduces the electrochemical performance. Therefore, it is urgent and significant to assist the MOFs with quite a few novel substrates (e.g., layered double hydroxides (LDHs), [30,31] graphene, [21] carbon cloth, [32] polyacrylonitrile (PAN) nanofibers, [33] and Te nanowires [29] ) to achieve the The exploitation of high-efficiency, cost-effective, and stable oxygen reduction reaction (ORR) electrocatalysts is extremely critical for energy storage and conversion technology. The transition metal carbonitrides have been investigated as an alternative to precious metal-based catalysts. Here, a series of uniform Co nanoparticles encapsulated in nitrogen-doped porous carbon fibers (Co@N-PCFs for brevity) are designed and synthesized by directly carbonizing the Zn x Co 1-x -zeolitic imidazolate frameworks@polyacrylonitrile (Zn x Co 1-x -ZIFs@PAN) electrospun nanofiber...