Group IVB transition metal (Zr and Hf) dichalcogenide (TMD) monolayers can have higher carrier mobility and higher tunneling current density than group VIB (Mo and W) TMD monolayers. Here we report the synthesis of hexagonal ZrS2 monolayer and few layers on hexagonal boron nitride (BN) using ZrCl4 and S as precursors. The domain size of ZrS2 hexagons is around 1-3 μm. The number of layers of ZrS2 was controlled by tuning the evaporation temperature of ZrCl4. The stacking angle between ZrS2 and BN characterized by transmission electron microscopy shows a preferred stacking angle of near 0°. Field-effect transistors (FETs) fabricated on ZrS2 flakes showed n-type transport behavior with an estimated mobility of 0.1-1.1 cm(2) V(-1) s(-1).

Two novel conjugated microporous networks, P-1 and P-2, with carbazole-spacer-carbazole topological model structures, were designed and prepared by FeCl 3 oxidative coupling polymerization. Monomer m-1 (fluorenone spacer) was modified with a thiophene Grignard to form the fluorenyl tertiary alcohol monomer m-2, and this step can increase the polymerization branches from four to five and incorporate the polar -OH group into the building block. N 2 adsorption isotherms show that, after modification, the Brunauer-Emmett-Teller (BET) surface area of P-2 (1222 m 2 g À1) is two times that of P-1 (611 m 2 gand the total pore volume increases 1.63 times from 0.95 to 1.55 at P/P 0 ¼ 0.99. However, the domain pore size (centred at 1.19 nm) and the pore distribution of both networks are not changed. It demonstrates that the domain pore width may be determined by the size of the rigid carbazole-spacercarbazole backbone, not the degree of crosslinking when the networks were prepared under same polymerization conditions in this system. Hydrogen physisorption isotherms of P-1 and P-2 show that the H 2 storage can be up to 1.05 wt% and 1.66 wt% at 77 K and 1.1 bar, and the isosteric heat is 9.89 kJ mol À1 and 10.86 kJ mol À1 , respectively. At 273 K and 1.1 bar, the CO 2 uptake capacity of P-2 can be up to 14.5 wt% which is 1.63 times that of P-1 under the same conditions. The H 2 and CO 2 uptake capacities of P-2 are among the highest reported for conjugated microporous networks under similar conditions. The CO 2 /CH 4 and CO 2 /N 2 selectivity results indicate that P-1 exhibits a slightly higher separation ability than P-2. There is often a trade-off between absolute uptake and selectivity in other microporous organic polymers. Fine design and tailoring the topological structure of the monomer can change the adsorption isosteric enthalpy and optimize the gas uptake performance. The obtained networks with the carbazole-spacer-carbazole rigid backbone show promise for potential use in clean energy applications and the environmental field.

As a new type of porous crystalline material, hydrogen-bonded organic frameworks (HOFs) assemble through intermolecular hydrogen bonds of organic building blocks. Unique advantages of HOFs, such as high crystallinity, solution...

Electrochemical water splitting is an important strategy for the mass production of hydrogen. Development of synthesizable catalysts has always been one of the biggest obstacles to replace platinum‐group catalysts. In this work, a high quality crystal polymer covalent triazine framework [CTF; Brunauer–Emmett–Teller (BET) surface area of 1562.6 m2 g−1] is synthesized and MoS2 nanoparticles are grown in situ into/onto the 1 D channel arrays or the external surface for electrocatalysis [hydrogen evolution reaction (HER)] . The state‐of‐the‐art CTFs@MoS2 structure exhibits superior catalytic kinetics with an overpotential of 93 mV and Tafel slope of 43 mV dec−1, which is improved over most other reported analogous catalysts. The inherent π‐conjugated crystal channels in CTFs provides a multifunctional support for electron transmission and mass diffusion during the hydrogen evolution process. Catalytic kinetics analysis shows that the HER performance is closely correlated to the hierarchical pore parameters and aggregated thickness of MoS2 nanoparticles. This work provides an attractive and durable alternative to synthesize high activity and stable catalysts for HER.

A novel phenyl substituted benzo(1,2‐b:4,5‐b’)dithiophene (BDT) derivative containing both fluorine and sulfur atoms is designed and synthesized. Furthermore, a wide bandgap polymer PBTA‐PSF based on the derivative shows a low highest occupied molecular orbital energy level and slightly reduces the donor materials’ optical bandgap, which has a complementary absorption with a narrow‐bandgap n‐type small molecule ITIC. As a result, a power conversion efficiency of 13.91% is achieved with a high open‐circuit voltage of 1.01 V, and a large short‐circuit current density of 18.51 mA cm−2. The result demonstrates that PBTA‐PSF is a promising candidate for high‐performance donor and phenyl‐containing BDT derivatives and has potential in the design of high‐performance polymers for organic photovoltaics.

Three new conjugated microporous polymers are synthesized with high CO2 and H2 uptake and great CO2/CH4 selectivity.

A series of crystalline, stable Metal (Metal = Zn, Cu, Ni, Co, Fe, and Mn)‐Salen covalent organic framework (COF) EDA complex are prepared to continuously tune the band structure of Metal‐Salen COF EDA , with the purpose of optimizing the free energy intermediate species during the hydrogen evolution reaction (HER) process. The conductive macromolecular poly(3,4‐ethylenedioxythiophene) (PEDOT) is subsequently integrated into the one‐dimensional (1D) channel arrays of Metal‐Salen COF EDA to form heterostructure PEDOT@Metal‐Salen COF EDA via the in situ solid‐state polymerization method. Among the Metal‐Salen COF EDA and PEDOT@Metal‐Salen COF EDA complexes, the optimized PEDOT@Mn‐Salen COF EDA displays prominent electrochemical activity with an overpotential of 150 mV and a Tafel slope of 43 mV dec −1 . The experimental results and density of states data show that the continuous energy band structure modulation in Metal‐Salen COF EDA has the ability to make the metal d ‐orbital interact better with the s ‐orbital of H, which is conducive to electron transport in the HER process. Moreover, the calculated charge density difference indicates that the heterostructures composed of PEDOT and Metal‐Salen COF EDA induce an intramolecular charge transfer and construct highly active interfacial sites.

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