ACS Applied Energy Materials
·
2023
·
IF 6.4
Lin Zhu,Cheng-long Ma,Li-mei Cao,Ji Yang
Here, two iridium-based crystal structures, K0.3IrO2·xH2O and Rb0.3IrO2·xH2O, have been synthesized for application in the oxygen evolution reaction (OER). The 3R-type layered IrO2 structures with different lattice parameters were successfully obtained from the two Ir structures by the hydrogen ion exchange method. According to synchrotron radiation spectra and the theoretical calculation of density functional theory (DFT), the increase of oxygen vacancy concentration caused by lattice distortion in the 3R-IrO2 crystal is negatively correlated with the activity of OER. A high concentration of oxygen vacancies will reduce Ir–O hybridization, which is not conducive to the balance between the adsorption and desorption of intermediate products. The higher OH adsorption energy barrier and band gap of the 3R-IrO2 crystal limited the improvement of electrochemical performance. In addition, through the analysis of the bonding orbitals and antibonding orbitals of the two structures, we concluded that 3R-IrO2 belongs to the nonthermodynamically stable structure and is not suitable for hydrogen production by electrolysis of water.
研究领域:
材料科学
·
理论化学
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产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2021
·
IF 5.316
Lin Yue,Yunmeng Cao,Yonghui Han,Zaixing Li,Xiao Luo,Yanfang Liu
The magnetic metal-organic framework composite Fe 3 O 4 @Sn-MOF with core-shell structure was successfully prepared by hydrothermal synthesis. It was characterized by XRD , TEM , BET, DRS , FT-IR, XPS and VSM. The photocatalytic performance of the composite was evaluated by degradation of Acid Red 3R (AR3R) dye under simulated light source. Under the conditions that the additive amount of the catalyst was 6.7 g/L, the initial concentration of AR3R was 50 mg/L and the initial pH of AR3R was 3.0, Fe 3 O 4 @Sn-MOF revealed the optimized photocatalytic activity with 100% degradation efficiency of AR3R at 30 min. The excellent photocatalytic ability was mainly ascribed to the effective charge separation, strong photo-response and rich active sites. Besides, using Fe 3 O 4 as the magnetic nucleus was conducive to improve the recovery rate of the catalyst. The EPR and free radical analysis indicate that •O 2 − and •OH played important roles in the photocatalytic reaction. Meanwhile, a possible degradation process and mechanism were proposed by the full band scanning of AR3R, 3D-EEM fluorescence analysis and electrochemical measurement.
研究领域:
材料科学
·
环境科学
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产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2025
·
IF 7.2
Shiting Li,Yuehan Wang,Chang Cai,Hong Huang,Honggen Peng,Xiaoxiao Fu,Zhimin Ao,Chunyang Nie
MoS 2 polytypes are emerging as compelling metal-sulfide catalysts for peroxymonosulfate (PMS) activation in water decontamination. The catalytic properties of the 1 T and 2H phases have been extensively explored, the performance of the 3 R polytype remains largely unknown. This work presents a comparative investigation of bulk 2H-MoS 2 and 3R-MoS 2 for activating PMS to remove phenol, with a specific focus on the understudied 3 R phase. A ball-milling pretreatment was employed to create sulfur vacancies, a critical active site, in both polytypes. Through a combined experimental and theoretical approach, we demonstrate that sulfur-defective 2H-MoS 2 exhibits superior catalytic activity for PMS activation, with a phenol degradation reaction rate constant 4.3 times higher than that of its 3 R counterpart. More importantly, we unveil that both polytypes activate PMS predominantly via a nonradical pathway mediated by surface Mo-PMS⁎ complexes, rather than generating free radicals. However, in-situ Raman spectroscopy and DFT calculations reveal that the distinct electronic structures of the two polytypes lead to the formation of Mo-PMS complexes with different configurations and oxidative capabilities, explaining their disparate selectivity towards various organic pollutants. This study provides the first mechanistic insight into PMS activation by 3R-MoS 2 and establishes that the crystal polytype is a critical, previously overlooked factor governing the efficiency and oxidation pathway in MoS 2 -based advanced oxidation processes, offering a vital guideline for selecting suitable MoS 2 catalysts in environmental applications.
研究领域:
环境催化
·
高级氧化工艺
·
材料科学
·
水处理
·
纳米材料
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产品关联
DOI
高影响因子
Biocatalysis and Agricultural Biotechnology
·
2019
·
IF 0
Feng-Qin Gong,Qi-Shun Liu,Hai-Dong Tan,Tang Li,Cheng-Yu Tan,Heng Yin
Acetoin (3-hydroxy-2-butanone) is an important four-carbon compound widely used in the food industry and other industrial applications. This study aimed to identify a novel butanediol dehydrogenase that can efficiently catalyze the formation of acetoin. A novel butanediol dehydrogenase, Bt BDH, was identified from Bacillus thuringiensis subsp. Kurstaki ACCC 10066, and its enzymatic properties were characterized. The optimum pH and temperature for the oxidation activity of Bt BDH were 10.0 and 50 °C, respectively, and those for the reduction activities were 7.5 and 35 °C, respectively. In addition, it exhibits stability over a wide pH range (6–10) and temperatures up to 70 °C. Bt BDH showed good stability after storage for 3 months at 4 °C. Moreover, ethylenediaminetetracetic acid (EDTA) inhibits the enzymatic activity of Bt BDH, indicating that the enzyme is metal-dependent. This study characterized a novel (2R,3R) −2,3-butanediol dehydrogenase. Its excellent oxidation activity and stability ensure its great industrial application potential in the production of acetoin.
研究领域:
生物化学
·
微生物学
·
酶学
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产品关联
DOI
BIOORGANIC CHEMISTRY
·
2025
·
IF 4.7
Xinqi Xu,Xialian Wang,Lian Xu,Bingmei Su,Juan Lin,Qiaobin Chen
Fe(II)/α-ketoglutarate (α-KG)-dependent isoleucine dioxygenase (IDO) enables selective C-H hydroxylation to produce the antidiabetic agent (2 S , 3 R , 4 S )-4-hydroxyisoleucine ((2 S , 3 R , 4 S )-4-HIL), but its industrial application is limited by insufficient activity and stability and the high cost of α-KG. Here, the IDO from Bacillus thuringiensis was engineered using multiple strategies to generate a mutant MU3 (V146I/S105E/N104P) with increased substrate loading. The specific activity exhibited 15-fold higher (152.0 U/mg) with 15-fold improved catalytic efficiency ( k cat / K m ) for L-isoleucine hydroxylation. The thermostability was enhanced with a 10-fold decrease in thermal inactivation rate at 30 °C. Molecular dynamics simulation revealed that the communication alteration between the loops around the active site and the strengthened substrate binding contributed to the improvement of MU3. The MU3 mediated L-isoleucine hydroxylation was coupled with an optimized whole-cell module integrating L-glutamate oxidase and catalase for α-KG generation from low-cost L-glutamate sodium. By the stepwise whole-cell biocatalytic cascade system, both 500 mM and 750 mM of L-isoleucine could be completely converted into (2 S , 3 R , 4 S )-4-HIL under scaled-up condition. The whole space-time-yield reached 196 g/L/d as the highest record up to date and the cost was decreased compared to the α-KG-supplemented approach. This work provides an efficient, cost-effective and scalable route for (2 S , 3 R , 4 S )-4-HIL synthesis.
研究领域:
酶工程
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生物催化
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合成生物学
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工业生物技术
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代谢工程
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产品关联
DOI
PubMed
高影响因子
Nano Materials Science
·
2024
·
IF 12.6
Liquan Fan,Honglin Ai,Meiye Jiao,Yao Li,Yongheng Jin,Yiru Fu,Jing Wang,Yuwei Wang,Deqing Zhang,Guangping Zheng,Junye Cheng
As electromagnetic technology advances and demand for electronic devices grows, concerns about electromagnetic pollution intensify. This has spurred focused research on innovative electromagnetic absorbers, particularly chalcogenides, noted for their superior absorption capabilities. In this study, we successfully synthesize 3R–TaS 2 nanosheets using a straightforward calcination method for the first time. These nanosheets exhibit significant absorption capabilities in both the C-band (4–8 GHz) and Ku-band (12–18 GHz) frequency ranges. By optimizing the calcination process, the complex permittivity of TaS 2 is enhanced, specifically for those synthesized at 1000 °C for 24 h. The nanosheets possess dual-band absorption properties, with a notable minimum reflection loss (RL min ) of −41.4 dB in the C-band, and an average absorption intensity exceeding 10 dB in C- and Ku-bands, in the absorbers with a thickness of 5.6 mm. Additionally, the 3R–TaS 2 nanosheets are demonstrated to have an effective absorption bandwidth of 5.04 GHz (3.84–8.88 GHz) in the absorbers with thicknesses of 3.5–5.5 mm. The results highlight the multiple reflection effects in 3R–TaS 2 as caused by their stacked structures, which could be promising low-frequency absorbers.
研究领域:
材料科学
·
电磁学
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DOI
高影响因子
RARE METALS
·
2023
·Vol. 42
·期 12
·3985-3992
·
IF 8.8
Yang Yang,Liang Qing-Rong,Zhu Chun-Li,Zheng Guo-Zhong,Zhang Jian,Zheng Shou-Jun,Lin Yung-Chang,Zheng De-Zhi,Zhou Jia-Dong
Van der Waals coupling with different stacking configurations can significantly affect the optical and electronic properties of ultrathin two-dimensional (2D) materials, which is an effective way to tune device performance. Herein, we report a salt-assisted chemical vapor deposition method for the synthesis of bilayer V-doped MoS 2 with 2H and 3R phases, which are demonstrated by the second harmonic generation and scanning transmission electron microscopy. Notably, the mobility of the 3R phase V-doped MoS 2 is 6.2% higher than that of the 2H phase. Through first-principles calculations, we further reveal that this particular behavior is attributed to the stronger interlayer coupling of 3R compared to the 2H stacking configuration. This research can be further generalized to other transition metal chalcogenides and will contribute to the development of electronic devices based on 2D materials in the future.
研究领域:
材料科学
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纳米科技
·
凝聚态物理
·
二维材料
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半导体材料
·
表面科学
·
计算材料学
✓ 已验证
DOI
高影响因子
RENEWABLE ENERGY
·
2022
·
IF 8.634
Qianqian Zhang,Lei Zhao,Fen Ran
Hydrogel electrolytes are attracting growing interest in the various fields, and tremendous efforts have been widely made for enhancing the hydrogel electrolyte of flexible devices. However, conventional hydrogel electrolytes generally contain non-degradable and non-renewable polymer matrix materials, inevitably causing waste of resources and environmental pollution, which fundamentally restricts the utilization of hydrogel electrolyte in the aspect of energy storage device during daily use. In this work, a novel flexible hydrogel electrolyte, that can be reducible, recyclable, and reusable (3R), is fabricated through physical and chemistry double crosslinking among carboxylated chitosan, N -methylol acrylamide, N, N′ -methylene bisacrylamide, and potassium persulfate, followed by intense uptake of Li 2 SO 4 electrolyte. The hydrogel electrolyte membrane displays high ionic conductivity of 3.52 × 10 −2 S cm −1 , and exhibits 348.92% electrolyte uptake., The flexible quasi-solid supercapacitor assembled with the hydrogel electrolyte shows remarkable electrochemical performance like high capacitance retention of 83% and outstanding energy density of 8.74 Wh kg −1 . Interestingly, the renewable performance of hydrogel electrolyte membrane is observed when the hydrogel electrolyte membrane suffered from heating to cooling cycle, which allows to easily realize multiple regeneration of electrolyte membrane based on the reversible sol-gel transition. This work provides a promising route to design a hydrogel electrolyte membrane with infinite regeneration times for flexible energy storage devices in the future.
研究领域:
材料科学
·
能源存储
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Water Process Engineering
·
2025
·
IF 6.7
Miao Huang,Wencong Li,Xiangdong Xu
With rapid increases of population and chemical discharge, treatment and recycling of wastewater have become increasing important. Herein, a new approach for ultrafast degradations of both organic and inorganic pollutants in wastewater by only piezocatalysis, triggered by low air pressure on MoS 2 , is described. Results reveal that the degradation rates of organic methylene blue and inorganic nitrite reach 99.5 % within 75 s and 91.5 % within 1200 s, with the first-order rate constants of 0.072 s −1 and 0.0016 s −1 , respectively. Both degradation rates are faster than those of other methods previously reported. And coexistence of organic and inorganic pollutants causes further enhancement of the piezocatalysis efficiency. Particularly, the piezocatalysis of commercial MoS 2 can be efficiently activated by this air-pressure approach, which is difficult to realize by previous others. The piezocatalytic degradations of other organic pollutants can be similarly induced. Moreover, higher degradation rates are measured in neutral or weakly alkaline environments, and high degradation efficiencies (> 90 %) can be similarly achieved in various water sources. Theoretical simulations support the experimental findings, both indicating a new, environment-friendly, and low-cost approach for efficiently activating the piezocatalysis of MoS 2 by low air pressure, thus leading to wastewater purification and energy conservation.
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DOI
高影响因子
MOLECULAR BIOTECHNOLOGY
·
2021
·Vol. 63
·期 6
·491-501
·
IF 2.695
Tang Wanggang,Lian Chaoqun,Si Yu,Chang Jianrong
2,3-Butanediol dehydrogenase (BDH), also known as acetoin/diacetyl reductase, is a pivotal enzyme for the formation of 2,3-butanediol (2,3-BD), a chiral compound with potential roles in the virulence of certain pathogens. Here, a NAD(H)-dependent (2 R ,3 R )-BDH from Neisseria gonorrhoeae FA1090 (NgBDH), the causative agent of gonorrhoea, was functionally characterized. Sequence analysis indicated that it belongs to zinc-containing medium-chain dehydrogenase/reductase family. The recombinant NgBDH migrated as a single band with a size of around 45 kDa on SDS-PAGE and could be confirmed by Western blotting and mass spectrometry. For the oxidation of either (2 R ,3 R )-2,3-BD or meso -2,3-BD, the enzyme exhibited a broad pH optimum between pH 9.5 to 11.5. For the reduction of (3 R /3 S )-acetoin, the pH optimum was around 6.5. The enzyme could catalyze the stereospecific oxidation of (2 R ,3 R )-2,3-BD ( K m = 0.16 mM, k cat / K m = 673 s −1 · mM −1 ) and meso -BD ( K m = 0.72 mM, k cat / K m = 165 s −1 · mM −1 ). Moreover, it could also reduce (3 R /3 S )-acetoin with a K m of 0.14 mM and a k cat / K m of 885 s −1 · mM −1 . The results presented here contribute to understand the 2,3-BD metabolism in N. gonorrhoeae and pave the way for studying the influence of 2,3-BD metabolism on the virulence of this pathogen in the future.
研究领域:
微生物学
·
生物化学
✓ 已验证
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2022
·
IF 9.136
Bo He,Zixuan Zhao,Lixian Song,Weibao Liu,Ying Yang,Jiangwei Shang,Xiuwen Cheng
The degradation of carbamazepine (CBZ) by activated peroxymonosulfate (PMS) using the (3R + 2H)-CuFeO 2 nanocomposite photocatalyst was investigated in this work. The (3R + 2H)-CuFeO 2 were prepared by hydrothermal method at 160°for 15 h utilizing ferrous sulphate heptahydrate (FeSO 4 ·7H 2 O) and copper (II) sulphate (CuSO 4 ·5H 2 O) as raw materials. Meanwhile, the (3R + 2H)-CuFeO 2 was characterized and analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), isothermal nitrogen adsorption (BET), and X-ray energy spectroscopy (EDS). The best removal effectiveness was 85.96% when critical factors such as the starting pH value, catalyst dosage, and PMS quantity were turned. The action of anions was then investigated further. The high catalytic efficiency was due to the synergistic impact of Fe 3+ /Fe 2+ and Cu 2+ /Cu + redox cycles. The plausible CAZ breakdown routes were postulated based on the results of the liquid chromatograph-mass spectrometer (LC-MS). Finally, we have studied the most probable of cation migration by the 3DBVSMAPPER program and BVEL calculation concept to correlate the structural characteristics of both materials and their ionic conductivity . The formed channel shows the uniform transport of ions, which can optimize the solid–liquid interface, hinder the influence of water molecules on the material, and protect the material.
研究领域:
环境科学
·
化学工程
·
材料科学
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产品关联
DOI
高影响因子
BIOCHEMICAL ENGINEERING JOURNAL
·
2017
·
IF 2.892
Ya-Jun Wang,Xiao-Peng Chen,Wei Shen,Zhi-Qiang Liu,Yu-Guo Zheng
In our previous work, we constructed a carbonyl reductase (CR) and glucose dehydrogenase (GDH) co-expression strain E. coli BL21(DE3)/pCDFDuet- gdh - cr , and a biocatalytic process of chiral diol t -butyl 6-cyano-(3 R ,5 R )-dihydroxyhexanoate ((3 R ,5 R )- 2 ) was established by using its free cells. Herein, a (3 R ,5 R )- 2 process with celite-polyethyleneimine (PEI)-glutaraldehyde (GA) immobilized E. coli BL21(DE3)/pCDFDuet- gdh - cr whole cells was developed for the first time. It was demonstrated that immobilization via cross-linking was preferred, and the optimized immobilization conditions were as follows: 0.6% (w/v) celite, 4% (w/v) PEI and 1% (w/v) GA, pH7. The immobilizate can be used at pH 7.0, 30 °C for intermittent 7 batch, yielding a total of 17.5 g (3 R ,5 R )- 2 per gram of celite-PEI-GAimmobilizates in de p (diastereomeric excess) >99.5%. Compared with the free cells, there was a dramatic improvement in celite- PEI-GA immobilizate stability and recyclability. In this way, a promising platform technology based on a combination of cells immobilization and multiple enzymes co-expression is constructed, enabling efficiently converting inexpensive prochiral ketones to high-valued chiral alcohols.
研究领域:
生物化学
·
酶工程
·
合成生物学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）