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A family of heterojunction photocatalysts C 60 /TpPa have been constructed from fullerenes (C 60) and TpPa-1 via in-situ solvothermal method firstly. The photocatalytic activity toward CO 2 of C 60 /TpPa has been evaluated through the gas-solid reaction system under pure CO 2 and low concentration CO 2 (10 %) atmosphere, respectively. The results show that the maximum CO formation rates for C 60 /TpPa are as high as 48.16 μmol·g−1·h−1 and 90.25 μmol·g−1·h−1 under pure CO 2 and 10 % CO 2 environment, respectively. The attractive experimental phenomenon is assigned to the existence of C O groups in TpPa-1. Due to the presence of Z-scheme heterojunction, the separation of photoexcited electrons and holes is effectively enhanced, and the photocatalytic performances are significantly improved. This work suggests that the construction of COF-based photocatalysts with heterojunction for efficient photoreduction of CO 2 is a promising strategy. [Display omitted] • It is the first work that combining C 60 with TpPa-1 build Z-scheme heterojunction photocatalysts. • Due to the presence of C O groups, C 60 /COF achieve higher performance in 10 % CO 2 environment. • Z-scheme heterojunction enhances the performances by improving the efficient separation of photo-excited electrons and holes. [ABSTRACT FROM AUTHOR]

The anhydrous proton conductivity of Im@IEF-11 resulting from the integration of imidazole and porous IEF-11 has been investigated, and the highest proton conductive value can reach up to 7.64 × 10−2 S cm−1. Furthermore, IEF-11 is also developed to reduce CO2 due to its reasonable structure and suitable energy band, and its CO formation rate is 31.86 μmol g−1 h−1. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) provide an ideal platform for loading various guests owing to their available space, and can be developed as a class of multifunctional materials. Herein, we cover the design and synthesis of two kinds of exchanged frameworks with multifunctional applications based on H3ImDC and In(NO3)3·2H2O through guest exchange inside the framework. The guest ammonium ion (NH4+) and [Ru(2,2′-bipyridine)3]2+ (Rubpy) are selected to exchange the dimethylammonium cation (Me2NH2+) encapsulated within In-MOF, giving birth to two kinds of new MOFs, named NH4+@In-MOF and Rubpy@In-MOF respectively. The proton conduction of NH4+@In-MOF and the CO2 photoreduction of Rubpy@In-MOF are investigated. Under different test conditions, the proton conductive behaviors of NH4+@In-MOF are evaluated and the best proton conductive value can reach up to 9.81 × 10−3 S cm−1. Compared to the original In-MOF, Rubpy@In-MOF exhibits a significantly enhanced CO2 photoreduction performance under a pure CO2 atmosphere. Furthermore, its photocatalytic activity is retained even under a 10% CO2 gas atmosphere, displaying a synergistic effect between Rubpy and In-MOF24 within Rubpy@In-MOF. [ABSTRACT FROM AUTHOR]

• MOF/COF hybrid photocatalysts are prepared through the simple grinding method. • TpPa/ZIF-8 photocatalysts exhibit excellent performances in pure and diluted CO 2. • The role of –OH groups on photocatalytic performances is proposed and verified. It remains challenging to design and synthesize porous crystalline photocatalysts for photocatalytic reduction CO 2 with high efficiency. Herein, a Schiff-based covalent organic framework (TpPa-1) is explored to combine with a metal–organic framework (ZIF-8) via a simple and fast method (the grinding method) firstly, generating a series of photocatalysts TpPa/ZIF-8. The photocatalytic performances of the as-synthesized photocatalysts TpPa/ZIF-8 are evaluated through a gas–solid reaction mode without photosensitizers and sacrificial agents, exhibiting excellent photocatalytic activities toward CO 2 in pure CO 2 and 10% CO 2 atmosphere, especially in 10% CO 2 environment. Therefore, the experimental result presents that TpPa/ZIF-8 can obtain the CO formation rates of 43.94 μmol·g−1·h−1 at a pure CO 2 environment and 84.87 μmol·g−1·h−1 in 10% CO 2 atmosphere, approximately 2 times and about 6 times larger than those of TpPa-1 in the pure CO 2 and 10% CO 2 atmosphere, respectively. The interesting phenomenon inspires us to investigate the structural factors affecting the photocatalytic activity, and hydroxyl groups from TpPa-1 are suspected to play an important role in the significantly improved photoreduction performance of CO 2 in 10% CO 2 atmosphere. The controlling examples TFPa/ZIF-8 without hydroxyl groups have also been prepared and evaluated their photoreduction performances in order to validate this hypothesis. The results clearly prove the hydroxyl groups tend to enhance CO 2 photoreduction. Additionally, it is noted that TpPa/ZIF-8 could maintain certain photocatalytic activity under the irradiation of sunlight. Summarily, the superior photocatalytic performances of TpPa/ZIF-8 may result from the high charge separation efficiency and increased photocatalytic active sites as well as the CO 2 adsorption capacity. The reported work sheds light on the construction of MOFs/COFs hybrid materials and expands their applications. [ABSTRACT FROM AUTHOR]

Development of new proton exchange membranes for fuel-cells draw considerable attentions. A family of proton conductive membranes based on poly(sodium 4-styrene sulfonate) (PSSNa) and polyvinylidene fluoride (PVDF) combining with various additives oxalic acid (OX), phosphate (PA) and phosphomolybdic acid H 3 PMo 12 O 40 ·XH 2 O (PMo 12) have been fabricated through a slurry casting approach, and are defined as PSSNa-PVDF-OX, PSSNa-PVDF-PMo 12 and PSSNa-PVDF-PA respectively, whose proton conductivities have been systematically investigated. Among them, PSSNa-PVDF-OX shows the superior proton conductivity, compared to PSSNa-PVDF-PA and PSSNa-PVDF-PMo 12 , and the best proton conductive value can reach up to 5.0 × 10−3 S cm−1 at 60 °C and 95% relative humidity, proving the good compatibility of OX with PSSNa and PVDF, giving birth to an effective proton transport channel. In order to demonstrate the role of Na+, poly(4-styrene sulfonic acid) (PSSA) is employed to replace PSSNa, generating another series of proton conductive membranes PSSA-PVDF-OX. The proton conductivity of PSSNa-PVDF-OX is greater than those of PSSA-PVDF-OX, which is attributed to the strong interactions between Na+ and water molecules, accelerating proton movement. Summarily, the enhanced conductivity is attributed to the generated efficient conduction pathways constructed from Na+ ions, water molecules, abundant -COOH from OX and -SO 3 - groups from PSSNa as well as rich F groups from PVDF. Several proton-conductive membranes are prepared with the best value of 5.0 × 10−3 S cm−1, demonstrating Na+ play an important role for high proton conduction. [Display omitted] • A series of composite membranes with various additives based on PSSNa and PVDF have been synthesized. • PSSNa-PVDF-OX60 shows superior performance and the best proton conductive value is 5.0 × 10−3 S cm−1 at 95% RH and 60 °C. • The introduction of Na+ builds the efficient transfer pathway for protons with OX, water as well as polymers. [ABSTRACT FROM AUTHOR]