RESEARCH ON CHEMICAL INTERMEDIATES
·
2018
·Vol. 44
·期 10
·5911-5922
·
IF 1.674
Yang Yingwei,Tang Ruiren
A practical method for the direct hydroxylation of benzene to phenol catalyzed by supported vanadium-substituted polyoxometalates using H 2 O 2 as an oxidant is described. Three vanadium-doped polyoxometalate Na 2 H 3 PMo 10 V 2 O 40 · x H 2 O catalysts were designed and prepared through support on graphitic carbon nitride (g-C 3 N 4 ), montmorillonite, and activated carbon and named as CN-PMoV 2 , M-PMoV 2 , and C-PMoV 2 , respectively. Their characterization was elucidated through the Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), inductively coupled plasma-atomic emission spectrometry (ICP-AES) and scanning electron microscopy (SEM). This heterogeneous catalyst demonstrated promising activity in the hydroxylation of benzene to phenol with H 2 O 2 . Especially, CN-PMoV 2 catalyst was highly active and selective even under mild conditions. Moreover, CN-PMoV 2 catalyst still has a certain catalytic effect even after three instances of repeated use.
研究领域:
化学
·
催化科学
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2025
·
IF 21.1
Bonan Li,Xi Zhang,Mengxue Chen,Xi Huang,Xiao Fang,Yanfang Yang,Yuanyuan Li,Baochun Ma,Yong Ding
Single-component metallic Te photocatalysts suffer from rapid oxidation in air, while sulfide-based SnS 2 is prone to photocorrosion under prolonged illumination, both severely limiting their photocatalytic efficiency. To address these challenges, we designed an S-scheme heterojunction by uniformly loading SnS 2 nanosheets onto Te nanowires (Te@SnS 2 ). This heterostructure not only suppresses Te oxidation but also facilitates efficient charge separation via the S-scheme mechanism. Further integration of [Co 4 (H 2 O) 2 (PW 9 O 34 ) 2 ] 10- (Co4POM) onto Te@SnS 2 yields the Te@SnS 2 -Co4POM photocatalyst, where Co4POM serves as a hole co-catalyst to enhance activity and inhibit SnS 2 photocorrosion. The system employs two discrete charge-transfer channels, with electrons separated at the Te@SnS 2 S-scheme heterojunction and holes migrating from SnS 2 to Co4POM, thereby spatially separating reduction and oxidation sites and markedly enhancing carrier separation, catalytic activity and durability. The multi-channel charge transfer pathways enabled by Te@SnS 2 -Co4POM synergize component interactions, achieving a CO production rate of 92.6 μmol g −1 h −1 with 97.7 % selectivity in gas-solid CO 2 reduction, alongside effective coupling of CO 2 photoreduction and water photooxidation. In situ DRIFTS, quasi-in situ XPS and irradiated KPFM studies confirm the S-scheme electron transfer in Te@SnS 2 and reveal Co4POM’s role in establishing multi-channel charge transport. This work demonstrates a rational strategy to overcome stability and efficiency bottlenecks in photocatalysis through multi-component charge channel engineering.
研究领域:
材料科学
·
光催化
·
环境科学
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
·
2023
·
IF 3.8
Hao Zhang,Pengfei Zhang,Zhiliang Liu,Chunfang Du
In this study, various silver phosphomolybdates ( x - y - z -AgPMo) with oxygen vacancies were successfully prepared through H 2 calcination and subsequent chemical precipitation and used for the adsorption of ciprofloxacin (CIP) in water. The microstructures of x - y - z -AgPMo were analyzed by a series of characterization methods. The effects of calcination time, calcination temperature, hydrogen flow rate, and external adsorption conditions on the adsorption performance were investigated. The results showed that the adsorption performance of 1–0.1–250-AgPMo toward CIP could reach 91% within 20 min with a maximum adsorption capacity of 45.5 mg∙ g − 1 , which was about 1.7 times as that of silver phosphomolybdate (Y-AgPMo) without H 2 calcination. The improved adsorption performance of 1–0.1–250-AgPMo was mainly attributed to the presence of oxygen vacancies, which induced more negative surface charges and larger specific surface area in 1–0.1–250-AgPMo. This work provided an excellent adsorbent for CIP removal and forcefully confirmed the important role of oxygen vacancies in the adsorption process.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
MOLECULES
·
2023
·Vol. 28
·期 8
·3398
·
IF 4.6
Na Li,Hongyue Zhang,Min Cui,Jujie Ren,Jingru Huang,Bao Sun,Haiyan Zhao,Cong Zhang
In this study, the preparation of covalent polyoxometalate organic frameworks (CPOFs) is introduced using the idea of polyoxometalate and covalent organic frameworks. Firstly, the prepared polyoxometalate was functionalized with an amine group (NH2-POM-NH2), and then the CPOFs were prepared by a solvothermal Schiff base reaction with NH2-POM-NH2and 2,4,6-trihydroxybenzene-1,3,5-tricarbaldehyde (Tp) as monomers. After the incorporation of PtNPs and MWCNTs into the CPOFs material, the PtNPs-CPOFs-MWCNTs nanocomposites, which possess excellent catalytic activity and electrical conductivity, were formed and utilized as new electrode materials for the electrochemical thymol sensors. The obtained PtNPs-CPOFs-MWCNTs composite exhibits excellent activity toward thymol, which is attributable to its large special surface area, good conductivity and the synergistic catalysis of each component. Under optimal experimental conditions, the sensor presented a good electrochemical response to thymol. The sensor shows two good linear relationships between the current and thymol concentration in the range of 2–65 μM (R2= 0.996) and 65–810 μM (R2= 0.997), with the corresponding sensitivity of 72.7 μA mM−1and 30.5 μA mM−1, respectively. Additionally, the limit of detection (LOD) was calculated to be 0.2 μM (S/N = 3). At the same time, the prepared thymol electrochemical sensor revealed superior stability and selectivity. The constructed PtNPs-CPOFs-MWCNT electrochemical sensor is the first example of thymol detection.Keywords:polyoxometalate;CPOFs;thymol sensor;electrochemistry
研究领域:
材料科学
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CRYSTENGCOMM
·
2020
·Vol. 22
·期 15
·2642-2648
·
IF 3.117
Ming-Yu Dou,Xian-Qiang Huang,Guo-Yu Yang
By the combination of Ag-complexes and Keggin POMs, two novel inorganic–organic silver–polyoxometalates hybrids, [Ag3L2(DMSO)2][PW12O40]·4DMSO (1) and [(Ag2L2)2][SiW12O40]·10DMSO·2H2O (2) (L = 4-(2-pyridyl)-6-(4-pyridyl)-2-aminopyrimidine), were synthesized and characterized. Interestingly, the silver atoms in compound 1 are three-coordinated with the AgNO model; however, the Ag atoms of compound 2 were surrounded by four N atoms of the organic ligands and displayed a distorted tetrahedral configuration. Importantly, compound 1 showed high catalytic activities for the three-component coupling reaction of alkynes and secondary amines along with formaldehyde, which resulted in a series of propargylamine derivatives in higher yields (up to 99%). Furthermore, the Ag–POM catalyst was easily recovered by filtration and reused for three cycles without a significant loss in catalytic activity. A tentative mechanism is also proposed for this transformation.
研究领域:
无机化学
·
有机化学
·
催化
✓ 已验证
产品关联
DOI
高影响因子
BIOMACROMOLECULES
·
2021
·
IF 6.988
Xiaohuan Liu,Zhiyuan Ma,Junlian Nie,Jun Fang,Wen Li
Recently, there has been a wave of reports on the fabrication of peptide-based underwater adhesives with the aim of understanding the adhesion mechanism of marine sessile organisms or creating new biomaterials beyond nature. However, the poor shear adhesion performance of the current peptide adhesives has largely hindered their applications. Herein, we proposed to sequentially perform the interfacial adhesion and bulk cohesion of peptide-based underwater adhesives using two redox-complementary peptide/polyoxometalate (POM) coacervates. The oxidative coacervates were prepared by mixing oxidative H5PMo10V2O40 and cationic peptides in an aqueous solution. The reductive coacervates consisted of K5BW12O40 and cysteine-containing reductive peptides. Each of the individual coacervate has well-defined spreading capacity to achieve fast interfacial attachment and adhesion, but their cohesion is poor. However, after mixing the two redox-complementary coacervates at the target surface, effective adhesion and spontaneous curing were observed. We identified that the spontaneous curing resulted from the H5PMo10V2O40-regulated oxidization of cysteine-containing peptides. The formed intermolecular disulfide bonds improved the cross-linking density of the dual-peptide/POM coacervates, giving rise to the enhanced bulk cohesion and mechanical strength. More importantly, the resultant adhesives showcased excellent bioactivity to selectively suppress the growth of Gram-positive bacteria due to the presence of the polyoxometalates. This work raises further potential in the creation of biomimetic adhesives through the orchestrating of covalent and noncovalent interactions in a sequential fashion.
研究领域:
材料科学
·
生物材料
·
化学
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2021
·
IF 5.455
Yupeng Zhai,Jialin Yu,Lijuan Zhang,Yunshan Zhou,Yuxu Zhong,Ying Yang,Yong’An Wang
In this study, an α-Keggin-type polyoxometalate H 5 PV 2 Mo 10 O 40 was loaded into the adamantane cage (18 Å) of MOF-808(Ce) by an immersion method to obtain composites with different polyoxometalate loadings. The effects of the H 5 PV 2 Mo 10 O 40 loading in the composite, the reaction time, and the quantity of the composite during the decontamination of the erosive agent surrogate, 2-chloroethyl ethyl sulfide (CEES) were investigated, and the optimized catalytic conditions for CEES were determined. The decontamination rate of 4 μL CEES reached 93.91% in 120 min using 40 mg of optimized composite, and the decontamination rate of 160 μL of the nerve agent surrogate, methyl paraoxon (DMNP) reached 100% in 25 min using 5 mg of the composite. Decontamination of CEES and DMNP by the composite followed first-order reaction kinetics. The half-life ( t 1/2 ) and kinetic rate constant ( k ) of these two reactions were 27.77 min and −0.02496 min −1 and 1.895 min and −0.36569 min −1 , respectively. The composite exhibited good decontamination performance after four replicate experiments. The results showed that CEES was oxidized to CEESO, while DMNP was hydrolyzed to p -nitrophenol and dimethyl phosphonate in the presence of the composite, showing that the proposed composite is an effective bifunctional catalyst for the selective oxidation and hydrolysis of chemical warfare agent surrogates.
研究领域:
材料科学
·
催化化学
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2020
·
IF 7.489
Gong Zhang,Jiaxing Zhang,Yuefei Wang,Yifei Wu,Qing Li,Yaoyu Liang,Wei Qi,Hengjun Rao,Rongxin Su,Zhimin He
In this work, we report a strategy to self-assemble multifunctional hydrogels composed of highly ordered polyoxometalates (POMs) helical arrays using a liquid crystalline tripeptide as the template. The cationic peptide can self-assemble into long-range ordered nanofilaments with a diameter of ~4.1 nm in aqueous media. Through the incorporation of various multivalent polyoxometalates (POMs), the POMs clusters can spontaneously organize into periodic nanowire arrays by the colloidal co-assembly with the as-prepared nematic peptide nanofilaments. This leads to the formation of hybrid gels with tunable mechanical strength by simply changing the charge number of the POMs. The H 3 PW 12 O 40 (noted as PW) clusters@peptide hybrid hydrogels show excellent adsorption performance of dyes. Moreover, the long-range aligned PW clusters within the co-assembled fiber bundles exhibit great improvement in the efficiency of photodegradation of dyes, which shows 8.7 times higher than that of the pristine PW clusters in the homogeneous phase. The synergistic effect between the adsorption and catalytic process within the hybrid gels is considered to be responsible for its highly catalytic activity. This work highlights a general pathway upon the well-defined organization of the various components into hybrid materials with superior properties using simple peptide liquid crystals as templates.
研究领域:
材料科学
·
化学
·
生物材料
✓ 已验证
DOI
PubMed
高影响因子
MOLECULES
·
2022
·Vol. 27
·期 9
·2933
·
IF 4.927
Yiran Wang,Fengxue Duan,Xiaoting Liu,Bao Li
Counter-cations are essential components of polyoxometalates (POMs), which have a distinct influence on the solubility, stabilization, self-assembly, and functionality of POMs. To investigate the roles of cations in the packing of POMs, as a systematic investigation, herein, a series of triol-ligand covalently modified Cu-centered Anderson-Evans POMs with different counter ions were prepared in an aqueous solution and characterized by various techniques including single-crystal X-ray diffraction. Using the strategy of controlling Mo sources, in the presence of triol ligand, NH4+, Cu2+and Na+were introduced successfully into POMs. When (NH4)6Mo7O24was selected, the counter cations of the produced POMs were ammonium ions, which resulted in the existence of clusters in the discrete state. Additionally, with the modulation of the pH of the solutions, the modified sites of triol ligands on the cluster can be controlled to form δ- or χ-isomers. By applying MoO3in the same reaction, Cu2+ions served as linkers to connect triol-ligand modified polyanions into chains. When Na4Mo8O26was employed as the Mo source to react with triol ligands in the presence of CuCl2, two 2-D networks were obtained with {Na4(H2O)14} or {{Na2(H2O)4} sub-clusters as linkers, where the building blocks were δ/δ- and χ/χ-isomers, respectively. The present investigation reveals that the charges, sizes and coordination manners of the counter cations have an obvious influence on the assembled structure of polyanions.Keywords:polyoxometalate;Anderson-Evans;triol ligand;cation-modulation
研究领域:
无机化学
·
材料科学
✓ 已验证
DOI
PubMed
高影响因子
MOLECULES
·
2022
·Vol. 27
·期 21
·7447
·
IF 4.927
Tian Chang,Di Qu,Bao Li,Lixin Wu
Vanadomolybdates (VMos), comprised of Mo and V in high valences with O bridges, are one of the most important types of polyoxometalates (POMs), which have high activity due to their strong capabilities of gaining/losing electrons. Compared with other POMs, the preparation of VMos is difficult due to their relatively low structural stability, especially those with unclassical architectures. To overcome this shortcoming, in this study, triol ligands were applied to synthesize VMos through a beaker reaction in the presence of V2O5, Na2MoO4, and organic species in the aqueous solution. The single-crystal X-ray diffraction results indicate that two VMo clusters, Na4{V5Mo2O19[CH3C(CH2O)3]}∙13H2O and Na4{V5Mo2O19[CH3CH2C(CH2O)3]}∙13H2O, with a similar architecture, were synthesized, which were both stabilized by triol ligand and {MoO6} polyhedron. Both clusters are composed of five V ions and one Mo ion in a classical Lindqvist arrangement with an additional Mo ion, showing an unprecedented hepta-nuclear VMo structure. The counter Na+cations assemble into one-dimensional channels, which facilitates the transport of protons and was further confirmed by proton conductivity experiments. The present results provide a new strategy to prepare and stabilize VMos, which is applicable for developing other compounds, especially those with untraditional architectures.Keywords:polyoxometalate;vanadomolybdate;triol ligand;covalent modification
研究领域:
无机化学
·
材料科学
✓ 已验证
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Jian Ji,Kebin Deng,Jianing Li,Zhihua Zhang,Xuezhi Duan,Haibao Huang
Despite substantial progress in various application fields of polyoxometalates (POMs), the use of POMs as ligands to alter the structure of solid catalysts in heterogeneous catalysis requires additional efforts. Herein, we used the reduced α-SiW 12 O 40 4- (RSTA) as an inorganic ligand to mediate Co 3 O 4 nanoparticles that efficiently promote the hydrolysis of NaBH 4 to generate hydrogen with multiple activities (4747 mL/(g cat ·min)) compared with NaBH 4 -pretreated Co 3 O 4 (1236 mL/(g cat ·min)), pristine Co 3 O 4 (inactive) and commercial Co 3 O 4 (inactive) at 25℃. RSTA induced both electronic and morphology effects on Co 3 O 4 through in situ driving 3D Co 3 O 4 nanoparticles to 2D Co 3 O 4 nanosheets with rich surface oxygen vacancies or Co 2+ during the hydrolysis process. This modulation by RSTA allowed more active sites, including both electron-rich Co 0 and electron-deficient Co 2+ , facilitating BH 4 - and H 2 O adsorption and thus hydrogen generation. The promoted mechanism of the RSTA on both the microstructure and the catalytic performance was further proposed.
研究领域:
催化化学
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2022
·
IF 9.965
Senda Su,Xiaoman Li,Xu Zhang,Jingting Zhu,Guodong Liu,Mengyao Tan,Yingying Wang,Min Luo
The incorporation of polyoxometalates (POMs) in metal-organic frameworks (MOFs) with host-guest structure have proven to be effective strategy to rational design of heterogeneous catalysis. In this study, the Keggin-type POM@MIL-101(Cr) composite catalysts (PMo 12 , PW 12 and SiW 12 ) are synthesized for nitrogen fixation reaction without sacrificial agents at room temperature in the first time. The SiW 12 molecules are encapsulated in smaller cavities of MIL-101(Cr) by solvothermal method and in larger cavities by impregnation method, respectively. Solvothermal synthesized catalyst has a performance of 75.56 μmol·h −1 ·g -1 cat and TOF value of 1.95 h −1 , which are about 10 and 88 times than that of Na 4 SiW 12 O 40 . The excellent performance is ascribed to the synergistic effect of SiW 12 and MIL-101(Cr). The MIL-101(Cr) adsorbs a large amount of N 2 and generates sufficiently photogenerated electrons under sunlight irradiation, and electrons quickly transfer to the SiW 12 through hydrogen bonds. Moreover, the agglomeration effect of the homogeneous catalyst SiW 12 is weakened due to encapsulation with more exposed active sites. This work provides a feasible route to design and synthesize nanocomposite materials with exceptional performance for photocatalytic nitrogen fixation.
研究领域:
材料科学
·
环境科学
·
化学
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）