Chem Catalysis
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2024
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IF 11.5
Bihua Hu,Bingxian Chu,Hailin Cao,Zhiwei Lei,Shuyu Cui,Peizhi Wang,Jun Tang,Xingzhu Wang,Baomin Xu
Molecular catalysts with precisely designed structures and abundant metal-nitrogen active sites have garnered significant attention for their ability to efficiently perform electroreduction of carbon dioxide (ERCD). However, the catalytic efficiency and selectivity are significantly limited by the fixed electronic structure of the metal-nitrogen structure, resulting in low production efficiency of more valuable products. This work presents the electronic regulation of cobalt phthalocyanine (CoPc) through in situ oxidation of N-doped Ti 3 C 2 T x nanosheets (CoPc/o–N–MXene). The resulting material exhibits high activity and tailorable selectivity. The study confirmed a strong interaction between Co-N 4 active sites and N–MXene after oxidation, resulting in a “Co–N–MXene” bond. This bond contributes to the transformation of intermediate ∗ CO into ∗ HCO, leading to a high selectivity of ERCD to methanol. This work provides a perspective on the mechanism of ERCD to methanol and an avenue for the synthesis of effective catalysts.
研究领域:
材料科学
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催化化学
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DOI
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
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2014
·Vol. 16
·期 24
·12008-12013
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IF 4.198
Yan Gao,Linlin Zhang,Xin Ding,Licheng Sun
Photoactive anodes consisting of Ru(bpy)3 type photosensitizer 1 and molecular catalysts 2 and 3 on nanostructured TiO2 have been assembled in functional devices for successful light driven water splitting. From their performance measurements we found that the photoanode TiO2(1 + 3) in which the molecular ruthenium catalyst and the phosphonate anchoring group are linked by a flexible –CH2CH2CH2– chain showed a significantly higher photocurrent density than the photoanode TiO2(1 + 2) with only –CH2– linkage. The possible reasons for the different water splitting performance of otherwise identical devices are discussed.
研究领域:
化学
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能源科学
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材料科学
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DOI
PubMed
高影响因子
RSC Advances
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2022
·Vol. 12
·期 17
·10460-10466
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IF 4.036
Zhichao Jin,Chunhua Yan,Huimin Chu,Qing Huang,Zhizhong Wang
Among the cyclodextrins screened for the synthesis of 2-hydroxy-1,2-diphenylethanone (benzoin) in water, 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) exhibited the highest yield in the benzoin condensation reactions, and HP-β-CD can be recycled several times with little loss of activity through the addition of fresh VB1. As an example of supramolecular catalysis, the methodology was applied to the “green” synthesis of the antiepileptic drug phenytoin through benzoin condensation, oxidation, and cyclization reactions in the presence of HP-β-CD, without the use of any harmful organic solvent. Moreover, the complexation behaviors of HP-β-CD with benzaldehyde and intermediates were studied by UV-vis and 2D-ROESY NMR spectroscopies to reveal the plausible mechanisms of the reactions, and HP-β-CD did not act as a simple phase transfer agent.
研究领域:
有机化学
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药物化学
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绿色化学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
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IF 16.744
Ye Meng,Yumei Jian,Jie Li,Hongguo Wu,Heng Zhang,Shunmugavel Saravanamurugan,Song Yang,Hu Li
The appropriate regulation of photocatalyst band structure by simultaneous introduction of active sites is an effective strategy in constructing efficient photocatalytic systems for biomass valorization. Herein, a renewed host–guest photocatalyst (Ov-WO 3 @CB[5]) prepared by anchoring cucurbit[5]uril on oxygen vacancy-rich WO 3 was efficient for reductive upgrading of biomass derivatives using NH 3 -BH 3 , such as cascade photocatalytic hydrogenation-cyclization of ethyl levulinate to γ-valerolactone (up to 99 % yield) at 25 °C in 1 h, and quantitative production of primary/secondary bio-alcohols or arylamines from various aldehydes/ketones or nitroarenes, respectively. Also, the rate of H 2 production by direct photocatalytic hydrolysis of NH 3 -BH 3 could reach 5.75 mL h −1 g −1 . The inclusion of cucurbit[5]uril effectively adjusted the semiconductor band structure and enhanced migration efficiency of photo-generated carriers, and the hydrophobic cavity of cucurbit[5]uril favored the entrance of NH 3 -BH 3 , as elaborated by theoretical calculations. Properly engineering supramolecular surface-active sites based on interface host–guest chemistry opens new avenues for reductive upgrading of biomass and hydrogen evolution.
研究领域:
化学
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能源科学
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材料科学
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DOI
高影响因子
MOLECULES
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2024
·Vol. 29
·期 3
·578
·
IF 4.2
Hengxin Jian,Mengyu Lu,Haowen Zheng,Shengrui Yan,Mei Wang
Mimicking the photosynthesis of green plants to combine water oxidation with CO2reduction is of great significance for solving energy and environmental crises. In this context, a trinuclear nickel complex, [NiII3(paoH)6(PhPO3)2]·2ClO4(1), with a novel structure has been constructed with PhPO32−(phenylphosphonate) and paoH (2-pyridine formaldehyde oxime) ligands and possesses a reflection symmetry with a mirror plane revealed by single-crystal X-ray diffraction. Bulk electrocatalysis demonstrates that complex1can homogeneously catalyze water oxidation and CO2reduction simultaneously. It can catalyze water oxidation at a near-neutral condition of pH = 7.45 with a high TOF of 12.2 s−1, and the Faraday efficiency is as high as 95%. Meanwhile, it also exhibits high electrocatalytic activity for CO2reduction towards CO with a TOF of 7.84 s−1in DMF solution. The excellent electrocatalytic performance of the water oxidation and CO2reduction of complex1could be attributed to the two uniqueµ3-PhPO32−bridges as the crucial factor for stabilizing the trinuclear molecule as well as the proton transformation during the catalytic process, while the oxime groups modulate the electronic structure of the metal centers via π back-bonding. Therefore, apart from the cooperation effect of the three Ni centers for catalysis, simultaneously, the two kinds of ligands in complex1can also synergistically coordinate the central metal, thereby significantly promoting its catalytic performance. Complex1represents the first nickel molecular electrocatalyst for both water oxidation and CO2reduction. The findings in this work open an avenue for designing efficient molecular electrocatalysts with peculiar ligands.Keywords:transition metal complex;water oxidation;carbon dioxide reduction;electrocatalysis;synergistic catalysis
研究领域:
化学
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环境科学
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能源科学
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产品关联
DOI
PubMed
高影响因子
Journal of Environmental Sciences
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2023
·
IF 6.9
Xiaofeng Cui,Xueting Wang,Lijun Zhao,Jixin Wang,Tingting Kong,Yujie Xiong
Homogenous molecular photocatalysts for CO 2 reduction, especially metal complex-based photosensitizer‒catalyst assemblages, have been attracting extensive research interests due to their efficiency and customizability. However, their low durability and recyclability limit practical applications. In this work, we immobilized the catalysts of metal terpyridyl complexes and the photosensitizer of [Ru(bpy) 3 ]Cl 2 onto the surface of carbon nanotubes through covalent bonds and electrostatic interactions, respectively, transforming the homogeneous system into a heterogeneous one. Our characterizations prove that these metal complexes are well dispersed on CNTs with a high loading (ca. 12 wt.%). Photocatalytic measurements reveal that catalytic activity is remarkably enhanced when the molecular catalysts are anchored, which is three times higher than that of homogeneous molecular catalysts. Moreover, when the photosensitizer of [Ru(bpy) 3 ]Cl 2 is immobilized, the side reaction of hydrogen evolution is completely suppressed and the selectivity for CO production reaches 100%, with its durability also significantly improved. This work provides an effective pathway for constructing heterogeneous photocatalysts based on rational assembly of efficient molecular photosensitizers and catalysts.
研究领域:
化学
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材料科学
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环境科学
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DOI
PubMed
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2024
·
IF 4.1
Yan Xu,Xinwang Zhu,Lan Ran,Xinyu Li,Shanyong Chen,Xiaoqing Qiu
Molecular catalysts have emerged as the promising candidate for oxygen reduction to hydrogen peroxide (H 2 O 2 ). Dispersing homogeneously molecular catalyst on carbon support is the prerequisite for actual electrocatalysis application. Herein, we proposed a novel strategy of modification with sodium dodecylbenzenesulfonate (SDBS) to improve dispersion of indium polyphthalocyanine (InPPc) on carbon nanotube (CNT). The SDBS modification induces the matched surface hydrophilicity of CNT with InPPc, preventing InPPc aggregation. As a result, the InPPc/SDBS@CNT exhibits a remarkable onset potential of 0.84 V vs. RHE and selectivity of > 95 %, superior to InPPc/CNT and most recently reported catalysts. In situ Raman spectrum identifies the critical *OOH intermediate during H 2 O 2 formation on InPPc/SDBS@CNT. Importantly, the InPPc/SDBS@CNT presents a prominent H 2 O 2 production rate of 24.88 mg/cm 2 /h over 12 h in flow cell. This work provides an effective strategy to promote practical application of molecular catalysts.
研究领域:
材料科学
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电化学
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催化化学
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DOI
高影响因子
ACS Sustainable Chemistry & Engineering
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2017
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IF 5.951
Yanjun Gong,Qiongzheng Hu,Yongxian Guo,Li Yu
We use an ionic self-assembly to build supramolecular catalysts using polyoxometalates (POM) and a common commercial surfactant with oppositely charged hexadecyltrimethylammonium bromide (CTAB). The supramolecular catalysts can dissolve in ionic liquid but become immiscible in water. On the basis of these properties, a new-style catalytic system was constructed by supramolecular catalysts and temperature-sensitive ionic liquid, tetrabutylphosphonium trifluoroacetate ([P4444][CF3COO]), in water. [P4444][CF3COO] aqueous solution can form a microemulsion at 298 K, and supramolecular catalysts can exist in the microemulsion phase. Phase separation occurs when the temperature is increased. So, the catalysts can be separated via the change in temperature. Moreover, supramolecular catalysts in ionic liquid can avoid poisoning in the catalytic process. This new-style catalytic system could be of great significance for cost savings in industry.
研究领域:
环境科学
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材料科学
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化学工程
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DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
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2024
·Vol. 142
·期 2
·e56337
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IF 2.7
ZiXuan Wang,Hao Zheng,Zhengchun Cai,Haian Xia
Bio-based plastics have received much attraction because they are an alternative to petroleum-based plastics in recent years. Among them, aliphatic polyesters have garnered the most attention due to their excellent properties. Polyester is primarily synthesized through ring opening polymerization of monomer, and the catalysts used are mostly synthesized through “click” reaction in the laboratory, which exhibits inferior activity and little commercial value. Herein, a facile approach was developed for the synthesis of high molecular-weight cyclic aliphatic polyesters, specifically poly(valerolactone- co -caprolactone) with varying compositions. This involved the ring-opening copolymerization of ε-caprolactone (ε-CL) and δ-valerolactone (δ-VL) in the absence of an initiator with commercial hydrogen bond donor triclorocarban and an organic base. The structure and properties of the prepared cyclic polyester were investigated using GPC, 13 C NMR, 1 H NMR, MALDI-TOF mass spectrometry, TOF-SIMS mass spectrometry, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and X-ray diffraction (XRD) techniques. The results show that the molecular weight of cyclic polyester can rapidly exceed 40 kDa, with a PDI of approximately 1.10. In comparison to linear polyester, it has a higher melting point and superior thermodynamic properties, thus presenting greater application potential. Finally, based on nuclear magnetic resonance titration, the potential catalytic processes and mechanisms of bimolecular systems on monomers in different environments were discussed. This study not only offers new insights into the structure and properties of cyclic polyesters, but also presents novel bimolecular catalytic systems using commercial urea hydrogen bond donors for the synthesis of cyclic polymer polyesters.
研究领域:
材料科学
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有机化学
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产品关联
DOI
高影响因子
Nano Energy
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2020
·
IF 16.602
Meirong Huang,Zhiwei Huang,Hongwei Zhu
Solar-driven photoelectrochemical water splitting is a promising solution to energy problem. However, not-yet-available long-term stability of photoelectrodes inhibits their practical application. Introducing structure tunable, highly active and easily prepared molecular catalysts is an efficient approach to improve their stability and has recently attracted great attention. Nonetheless, the long-term stability is still challenged due to regeneration of molecular catalyst during stability test. Herein, tannic acid coordinated with Ni and Fe ions (TANF) molecular catalyst is immobilized on BiVO 4 photoanode for oxygen evolution reaction (OER). Taking advantage of the regeneration of molecular catalyst, effects of buffer species on activity, stability and regeneration of TANF/BiVO 4 photoanodes are investigated. In an optimal borate electrolyte, the TANF/BiVO 4 photoanode shows nearly no-decay after operating at harsh conditions (at 1.2 V RHE with continuous light illumination) for 62 h. The long-term stability profits from the regenerated catalyst, which is composed of a carbon conductive network with metal oxides/hydroxides as OER-active sites. This excellent stability of the integrated photoanode surpasses most of existing OEC/BiVO 4 photoanodes, and the stabilized catalyst is comparable with the state-of-the-art FeOOH/NiOOH dual-cocatalyst and ferrihydrite catalyst.
研究领域:
材料科学
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能源化学
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DOI
高影响因子
Frontiers in Chemistry
·
2018
·
IF 4.155
Zeng Mengyan,Chen Kun,Tan Junyan,Zhang Jie,Wei Yongge
Oxidizing aldehydes to generate carboxylic acids is a crucial reaction in nature and in chemical industry. The aldehyde oxidation, an easily achieved process in liver cells, is inert toward autoxidation in industrial production and difficultly achieved under enzymatic condition (in water, at pH 7, at room temperature). Herein, we prepared a supramolecular catalyst which are nanospheres assembled in aqueous media by chromium centered Anderson polyoxometalates Na3[CrMo6O18(OH)3] (namely, CrMo6) and cationic pillar[5]arenes (namely, P5A) with 10 positive charges which can be used as the phase transfer catalysts (PTCs). This supramolecular catalyst was exploited on aldehydes oxidation under enzymatic condition with relatively good conversion. Through DLS monitoring, the diameters of nanospheres were variable while changing the charge ratios of the ionic complexes (P5A-CrMo6), and it is probably because of the closer charge ratios causing the more compact assemblies. Also, the nano-morphologies were monitored by TEM and SEM, and the nanostructures were characterized by zeta potential, the X-ray energy-dispersive spectroscopy (EDS), elemental analysis.
研究领域:
化学
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生物化学
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材料科学
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产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2019
·
IF 14.229
Xiangdong Kong,Yan Liu,Pai Li,Jingwen Ke,Zhongyu Liu,Fawad Ahmad,Wensheng Yan,Zhenyu Li,Zhigang Geng,Jie Zeng
As CO 2 coordination with the metal sites in molecular catalysts represents an effective means to CO 2 activation, it is important to develop molecular catalysts with high ability of CO 2 coordination to enhance their catalytic performance in CO 2 electroreduction. Herein, we investigated the coordinate activation of CO 2 with Co-based molecular catalysts by manipulating their ligand structures. During CO 2 electroreduction, the current density of Co-salophen for CO was −16.0 mA cm −2 at −0.75 V versus reversible hydrogen electrode ( vs RHE), which was 7.6 times of that (−2.1 mA cm −2 ) of Co-salen. In addition, the Faradaic efficiency (FE) of Co-salophen for CO reached 75 % at −0.70 V vs RHE, whereas the FE of Co-salen for CO production was 19 %. In-situ experiments and mechanistic studies revealed that both Co-salophen and Co-salen adopted a side-on coordination of CO 2 with Co sites. Moreover, the bonding between CO 2 and Co sites was strengthened in Co-salophen, resulting in the enhanced activity of Co-salophen.
研究领域:
化学
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催化科学
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DOI
高影响因子
危险品化学品经营许可证（带存储）