INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2021
·
IF 5.816
Shubo Wang,Yuan Lin,Jian Yang,Lei Shi,Guang Yang,Xupin Zhuang,Zhenhuan Li
Metal–organic frameworks (MOFs) exhibit high proton conductivity , thermal stability, and offer immense flexibility in terms of tailoring their size. Owing to their unique characteristics, they are desirable candidates for proton conductors . Nevertheless, constructing ordered MOF proton channels in proton exchange membranes (PEMs) remains a formidable challenge. Herein, blend nanofibers of cellulose and UiO-66-NH 2 (Cell–UiO-66-NH 2 ) obtained via the electrospinning process were embedded in a sulfonated polysulfone matrix to obtain high-performance composite PEMs with an orderly arrangement of UiO-66-NH 2 . Comprehensive characterization and membrane performance tests reveal that composite membrane with 5 wt% (nominal) UiO-66-NH 2 have revealed high proton conductivity of 0.196 S cm −1 at 80 °C and 100% relative humidity. Meantime, the composite membrane exhibits a low methanol permeability coefficient (~5.5 × 10 −7 cm 2 s −1 ). Moreover, the composite membrane exhibits a low swelling ratio (17.3%) even at 80 °C. The Cell–UiO-66-NH 2 nanofibers exhibit strong potential for use as a proton-conducting nanofiller in fuel-cell PEMs.
✓ 已验证
产品关联
DOI
高影响因子
DALTON TRANSACTIONS
·
2021
·Vol. 50
·期 17
·5943-5950
·
IF 4.39
Lu Feng,Jirong Lan,Fangyuan Chen,Haobo Hou,Hong Zhou
Metal–organic frameworks (MOFs), as a new class of proton conductors, have attracted much attention in the application of proton exchange membranes due to their precisely defined structure and tailorable functionality. However, for most of the MOF materials, their long-term stability is a huge barrier to practical application. Therefore, the structural stability of MOFs is an important prerequisite for the design and development of proton conductors with ultra-high conductivity. In this study, the stable UiO-66-NH2 is optimized as the precursor, and the modified material of DT-UiO-66 is designed and developed by introducing the 3,5-diamino-1,2,4-triazole molecule into the framework of UiO-66-NH2 through a post-synthesis strategy. Satisfactorily, DT-UiO-66 maintains the stability of the original skeleton. The alternating current impedance measurements indicate that a significantly improved proton conductivity of 4.47 × 10−3 S cm−1 is obtained at 100% relative humidity (RH) and 373 K for DT-UiO-66, which is attributed to the increasing number of proton sources and hopping sites. Moreover, DT-UIO-66 shows an outstanding stability under high temperature and high humidity conditions for at least 16 h, suggesting its potential application as a proton exchange membrane.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Sustainable Energy & Fuels
·
2021
·Vol. 5
·期 16
·4053-4059
·
IF 6.367
Xu Zhang,Xiaoman Li,Wanguo Gao,Shijian Luo,Senda Su,Rong Huang,Min Luo
Metal node substitution in metal organic frameworks is an efficient strategy to enhance their photocatalytic properties. Herein, bimetallic CeZr5-MOF UiO-66 photocatalysts were successfully synthesized by partially replacing Zr with Ce for enhancing the photocatalytic N2 reduction reaction (NRR). The rare earth element Ce was introduced into the node of Zr-MOFs (UiO-66) to form CeZr5 clusters, which enhanced the efficiency of photoexcited electron–hole pair separation and charge transfer via the ligand-to-metal charge transfer process (LMCT), thus promoting the photocatalytic nitrogen fixation performance. Photocatalytic properties increase linearly with the increase of Ce content. Higher Ce proportions (>20%) resulted in new MOFs (Ce-BDC-24) with low photocatalytic activity. The bimetallic system showed enhanced photocatalytic activities for N2 reduction, which was 105.9% higher than that of Zr-UiO-66 and reached 200.13 μmol g−1 h−1. Furthermore, the possible energy transfer mechanism was proposed to explain the photo-induced charge transfer process in the bimetallic UiO-66(CeZr5) system.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 137
·期 36
·49068
·
IF 2.52
Bing Liu,Dan Li,Jie Yao,Hao Sun
Branched polyethyleneimine (PEI) functionalized UiO-66 were synthesized and used as fillers to fabricated mixed-matrix membranes (MMMs) for CO 2 /CH 4 separation. The purpose of introducing amino-functional groups in the filler is to improve the interfacial compatibility of the filler with the polymer through the formation of hydrogen bonds with the carbonyl group of 6FDA-ODA. Additionally, the amino group can facilitate CO 2 transport through a reversible reaction, enhancing the CO 2 /CH 4 separation properties of MMM. The chemical structure and morphology of fillers and membranes were characterized by employing X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectrometer (FTIR), X-ray diffraction (XRD), thermogravimetric (TGA), Derivative thermogravimetry (DTG) and scanning electron microscope (SEM). Furthermore, the effects of filler loading and feed pressure on CO 2 permeability and CO 2 /CH 4 selectivity have been investigated. MMMs present higher gas separation performance than pure 6FDA-ODA due to the presence of amino groups and the improvement of interface morphology. In particular, the MMM with 15 wt% loading of UiO-66-PEI shows optimum CO 2 permeability of 28.23 Barrer and CO 2 /CH 4 selectivity of 56.49. Therefore, post-synthetic modification of UiO-66 particle with PEI is a promising alternative to improved membrane performance.
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2020
·Vol. 8
·期 16
·7870-7879
·
IF 11.301
Rongming Xu,Qinghua Ji,Pin Zhao,Meipeng Jian,Chao Xiang,Chengzhi Hu,Gong Zhang,Chaochun Tang,Ruiping Liu,Xiwang Zhang,Jiuhui Qu
Metal–organic frameworks (MOFs) have attracted increasing interest for adsorption applications due to their ultrahigh porosity and specific surface area. However, their adsorption performance in liquids, particularly for water treatment, is significantly limited by the poor accessibility of micropores inside the MOF matrix to most molecules and deficient active sites. Herein, we use a facile strategy, ligand selective thermolysis, to create oxygen vacancies and construct mesopores in water stable UiO-66. The obtained hierarchically porous UiO-66 (HP-UiO-66) has tunable oxygen vacancies and mesopores, and outperforms the state-of-the-art MOF based adsorbents reported so far in removing arsenic, achieving an ultrahigh adsorption capacity of 248.75 mg g−1 under neutral conditions. Extended X-ray absorption fine structure (EXAFS) and X-ray absorption near-edge structure (XANES) analysis and density functional theory (DFT) calculations reveal that arsenic is mainly captured by forming bidentate Zr–O–As bonds between arsenate and HP-UiO-66 via occupying coordinatively unsaturated zirconium atoms. This study offers a new strategy for designing ultrahigh performance MOF based adsorbents.
✓ 已验证
产品关联
DOI
高影响因子
Advanced Composites and Hybrid Materials
·
2021
·Vol. 4
·期 4
·1330-1342
·
IF 5.693
Zhang Fuhao,Cheng Wei,Yu Zhuanghua,Ge Shengsong,Shao Qian,Pan Duo,Liu Bin,Wang Xiaojing,Guo Zhanhu
A novel nanocomposite (WO 3 /UiO-66) was successfully synthesized by the microwave hydrothermal method. The influence of the W:Zr molar ratio on the WO 3 /UiO-66 structure was explored in detail, and the photocatalytic activity of the nanocomposite for photodegradation of rhodamine B (RhB) was evaluated. The WO 3 /UiO-66 with a W:Zr molar ratio of 1:5 (WO 3 /UiO-66–5) exerted the most excellent photocatalytic performance, and the photocatalytic efficiency reached 96.6% after 100 min of simulated sunlight irradiation, thereby showing a higher photocatalytic performance than pure UiO-66 or pure WO 3 . In addition, the stability and reusability of the nanocomposite were studied by cyclic experiments, and the degradation rate of WO 3 /UiO-66–5 still reached 86.6% after 5 cycles. The mechanism underlying the photocatalytic degradation of WO 3 /UiO-66 was finally studied by quenching tests, and the crucial factor in the RhB degradation was hole (h + ), and the existence of the n–n heterojunction also promotes the degradation of RhB by nanocomposites. In this work, an effective method is provided for the preparation of photocatalysts that degrade organic dyes.
✓ 已验证
产品关联
DOI
高影响因子
CRYSTENGCOMM
·
2019
·Vol. 21
·期 11
·1772-1779
·
IF 3.382
Zheng Deng,Xinsheng Peng,Yu-Jia Zeng
Modulators were frequently employed to synthesize UiO-66 with improved crystallinity, enhanced porosity, and controlled size and morphology. However, little attention was paid to the functionality of modulators themselves. We showed that ferrocenecarboxylic acid (FcCOOH) was not only an efficient modulator for UiO-66 synthesis but also endowed UiO-66 with redox properties. FcCOOH significantly reduced the size of UiO-66 from 400 nm intergrown crystals into 50 nm individual ones, and at the same time remarkably improved their crystallinity, micro-pore volume (0.56 cm3 g−1), and BET surface area (1364 m2 g−1). In addition, FcCOOH in UiO-66 served as a reducing agent for in situ incorporation of Pd nanoparticles into UiO-66 under mild conditions and was used as an efficient heterogeneous catalyst for the Suzuki–Miyaura reaction.
✓ 已验证
产品关联
DOI
高影响因子
CATALYSIS LETTERS
·
2015
·Vol. 146
·期 1
·117-125
·
IF 2.307
Dong Wenhuan,Feng Cheng,Zhang Li,Shang Ningzhao,Gao Shutao,Wang Chun,Wang Zhi
Abstract
In this paper, the palladium nanoparticles were successfully encapsulated in metal–organic framework material, UiO-66, by a facile approach. Based on the microwave-assisted method, the pores of UiO-66 were activated and the metal precursors were reduced at the same time in the presence of reducing agent. The obtained Pd@UiO-66 was characterized via transmission electron microscopy, powder X-ray diffraction, N 2 adsorption and X-ray photoelectron spectroscopy. The Pd@UiO-66 exhibited efficient catalytic activity for the Suzuki–Miyaura coupling reactions at mild condition. Graphical Abstract The palladium nanoparticles were successfully encapsulated in metal–organic framework material, UiO-66, by a facile approach. Based on the microwave-assisted method, the pores of UiO-66 were activated and the metal precursors were reduced at the same time in the presence of reducing agent. The obtained Pd@UiO-66 exhibited efficient catalytic activity for the Suzuki–Miyaura coupling reactions at mild condition.
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2015
·Vol. 6
·期 5
·3671-3679
·
IF 3.84
Aoning Wang,Yingjie Zhou,Zhoulu Wang,Miao Chen,Luyi Sun,Xiang Liu
A UiO-66-type metal–organic framework (MOF) fabricated with titanium was successfully prepared via a facial modified post-grafting method. The as-prepared samples were characterized by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), ultraviolet-visible adsorption spectroscopy (UV-vis), and photoluminescence spectroscopy (PL) techniques. The introduction of titanium enhanced the optical properties of UiO-66 via the formation of oxo-bridged hetero-Zr–Ti clusters, but led to a sacrifice in crystallinity. The removal of methylene blue (MB) over these samples could be attributed to the dual function of the adsorption and photo-degradation mechanisms. The highest MB removal efficiency of 87.1% was achieved over UiO-66(1.25Ti) under simulated sun-light irradiation.
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2017
·
IF 2.446
Aisheng Huang,Linlin Wan,Jürgen Caro
In a detailed study, the influence of microwave irradiation, synthesis time and temperature, addition of acetic acid (HAc) as a modulator on the morphology, crystallinity and stability of UiO-66-NH 2 is investigated to develop a reliable and reproducible strategy for the preparation of well-shaped UiO-66-NH 2 . The UiO-66-NH 2 were characterized by powder X-ray diffraction (PXRD), field emission scanning electron microscopy (FESEM), thermogravimetric analysis (TGA), and gas adsorption. It is found that well-shaped UiO-66-NH 2 with a high CO 2 adsorption capacity can be synthesized in a short time by microwave heating. The UiO-66-NH 2 crystals synthesized by microwave heating are of high quality and show a superior CO 2 adsorption capacity (5.8 mmol/g at 273k and 1 bar) due to the strong interactions between the −NH 2 group and CO 2 . The CO 2 /N 2 selectivity of the obtained UiO-66-NH 2 at 298 K and 1 bar is 66, which is much higher than that of the pristine UiO-66 of 17.8.
✓ 已验证
产品关联
DOI
高影响因子
Surfaces and Interfaces
·
2024
·
IF 5.7
Pengfei Zhu,Shuang Qin,Mengrong Geng,Heyang Cao,Zhiliang Jin,Chuanyi Wang
Photocatalytic NO removal technology is considered as one of the most effective green methods for reducing atmospheric NO but there remains the problems of lower efficiency and poor stability of photocatalysts . Rapid recombination of photogenerated electron (e − ) and holes (h + ) is known as a key issue that causes low activity and poor stability of catalysts. Herein, we report a novel AgCu@UiO-66-NH 2 photocatalyst (AgCu@UN) that is made up of AgCu alloy on the surface of Zr-MOF (UiO-66-NH 2 ) by employing in-situ photodeposition method. The experimental results of photocatalytic NO removal indicated that the optimized 0.5Ag0.5Cu@UN sample with 0.5 mg of Ag and Cu exhibited the best NO removal efficiency of 63 % for ppb-level atmospheric NO, more higher than that of pure UiO-66-NH 2 (38 %). The characterizations suggested that the excellent photocatalytic performance of 0.5Ag0.5Cu@UN can be ascribed to the efficient charge separation and transfer and the visible-light-harvesting ability due to benefiting electron migration process between AgCu alloys and UN. Moreover, the enriched electrons around AgCu could be transferred to O 2 to generate more superoxide radicals (•O 2 − ), which could oxidize NO to the final product, nitrate (NO 3 − ). The present findings can provide some novel insights for the design of efficient MOF based photocatalysts to eliminate low concentrations of NO X .
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2018
·
IF 5.091
Liang Zeng,Ling Xiao,Yangke Long,Xiaowen Shi
In this study, POM@UiO-66 nanoparticles were fabricated by encapsulation of POM (K 6 P 2 W 18 O 62 polyoxometalate) into mesoporous UiO-66 metal organic framework through a solvothermal method with trichloroacetic acid as a modulator to promote the defects formation of UiO-66. The as-prepared samples were characterized by TEM , SEM, PXRD , TG, XPS , and EDX elemental mapping, and the successful combination of POM and UiO-66 was confirmed. Two cationic dyes, rhodamine B and malachite green , and one anionic dye orange G were employed to investigate the adsorption performance of POM@UiO-66. The adsorption data showed that the removal process of cationic dyes by POM@UiO-66 matched well with the pseudo-second-order model and Langmuir isothermal model. The resulting POM@UiO-66 nanoparticles exhibited high adsorption to cationic dyes but low adsorption to anionic dyes, and the adsorption capacities of rhodamine B, malachite green, and anionic dye orange G were 222.6, 190.6 and 40 mg g −1 , respectively. Furthermore, the cationic dyes could be selectively removed from a cationic-anionic dye binary system. These results suggested that the novel polyoxometalate-based UiO-66 material is a promising candidate for the adsorption of cationic dyes from effluent.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）