APPLIED SURFACE SCIENCE
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2022
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IF 7.392
Binshu Sun,Jianhong Zheng,Dewu Yin,Huile Jin,Xin Wang,Quanlong Xu,Aili Liu,Shun Wang
Cocatalyst can greatly facilitate the charge separation efficiency and decrease the activation barrier of a specific reaction, thus contributing the improved photocatalytic performance. Herein, PdS/CdS/MoS 2 was synthesized via a facile microwave-assisted approach. Owing to the coexistence of PdS and MoS 2 , respectively serving as oxidation and reduction cocatalyst, PdS/CdS/MoS 2 displayed enhanced photocatalytic performance in both hydrogen production (6610 μmol·g −1 ·h −1 ) and benzylamine oxidation (87% conversion) in comparison with the individual and binary composite counterparts. The improved photocatalytic activity was mainly attributed to the high charge separation efficiency and lowed activation barrier. Furthermore, the introduction of PdS can timely extract photogenerated holes from CdS, which effectively inhibits the photo-corrosion of CdS, endowing it with high stability. This work paves the way for developing efficient chalcogenide photocatalysts.
研究领域:
材料科学
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光催化技术
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
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2022
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IF 4.889
Wenchao Zheng,Zuyi Yan,Rui Zhang,Wusan Jiang,Xiao Luo,Zhiwu Liang,Qi Yang,Hai Yu
The kinetics between BZA and CO 2 were investigated by the stopped-flow apparatus over the BZA concentration range from 0.05 to 0.1 mol/L (0.54–1.07 mass%), and over the temperature range from 293 to 313 K. The results also show that the predicted CO 2 absorption rate exhibits good agreement with the experimental data with an absolute average deviation (AAD) of 5.15% and 4.15% with respect to the zwitterion and termolecular models, respectively. Furthermore, the NMR experiments confirmed the formation of carbamates. The VLE plots were made with speciation data obtained from NMR techniques applied to the CO 2 -BZA-H 2 O system with CO 2 loading of 0–0.67 mol CO 2 /mol BZA at 298 K. A new VLE model was proposed, and the predicted results exhibit good agreement with the experimentaly measured results.
研究领域:
化学工程
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环境科学
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产品关联
DOI
高影响因子
Green Energy & Environment
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2022
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IF 12.781
Xiuzheng Zhuang,Jianguo Liu,Longlong Ma
Since the utilization of abundant biomass to develop advanced materials has become an utmost priority in recent years, we developed two sustainable routes (i.e., the impregnation method and the one-pot synthesis) to prepare the hydrochar-supported catalysts and tested its catalytic performance on the reductive amination. Several techniques, such as TEM, XRD and XPS, were adopted to characterize the structural and catalytic features of samples. Results indicated that the impregnation method favors the formation of outer-sphere surface complexes with porous structure as well as well-distributed metallic nanoparticles, while the one-pot synthesis tends to form the inner-sphere surface complexes with relatively smooth appearance and amorphous metals. This difference explains the better activity of catalysts prepared by the impregnation method which can selectively convert benzaldehyde to benzylamine with an excellent yield of 93.7% under the optimal reaction conditions; in contrast, the catalyst prepared by the one-pot synthesis only exhibits a low selectivity near to zero. Furthermore, the gram-scale test catalyzed by the same catalysts exhibits a similar yield of benzylamine in comparison to its smaller scale, which is comparable to the previously reported heterogeneous noble-based catalysts. More surprisingly, the prepared catalysts can be expediently recycled by a magnetic bar and remain the satisfying catalytic activity after reusing up to five times. In conclusion, these developed catalysts enable the synthesis of functional amines with excellent selectivity and carbon balance, proving cost-effective and sustainable access to the wide application of reductive amination.
研究领域:
催化化学
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生物质利用
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材料科学
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产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
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2017
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IF 6.844
Kewei Wang,Zhifang Jia,Xuekang Yang,Ling Wang,Yanlong Gu,Bien Tan
Heterogeneous microporous acid (sulfonic acid) and base (benzylamine) catalysts with high surface areas were synthesized using simple aromatic compounds through one-step external cross-linking reaction. The direct induction and control of catalytic sites were achieved by functionalized monomers using an appropriate amount of acid/base monomers. This strategy provides an easy approach to produce highly stable and acid/base functionalized microporous organic polymers. The structure and composition of the catalysts were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), nitrogen sorption, Fourier transform infrared spectroscopy (FT-IR), solid-state 13 C cross polarization magic angle spinning (CP/MAS) NMR, thermogravimetric analysis (TGA), and element mapping analysis. The stable porous skeleton and the accurate manipulation of the catalyst structure allowed us to use the obtained polymers as compatible and efficient acid/base co-catalysts for one-pot cascade reactions. We demonstrated the use of these microporous heterogeneous catalysts for the cascade deacetalization/Henry and deacetalization/Knoevenagel reactions. The results demonstrated that preparing microporous materials from simple aromatic compounds through one-step external cross-linking reaction is indeed a cost-effective and easy-to-handle method to produce functionalized heterogeneous catalysts. The microporous heterogeneous catalysts produced by this method are highly stable and the amount of catalytically active sites can easily be controlled to form a catalytic system with two antagonistic centers.
研究领域:
催化化学
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材料科学
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有机合成
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
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2018
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IF 6.14
Yuanyuan Chai,Lu Zhang,Qianqian Liu,Fengli Yang,Wei-Lin Dai
Oxidation of amines to imines under light irradiation has been widely studied in the field of heterogeneous catalysis. For the first time, we demonstrate a facile mixing calcination approach for the preparation of CeO2/g-C3N4-x as a heterojunction catalyst for the photo-oxidative coupling of benzylamine under the irradiation of a 300 W Xe arc lamp at 308 K with the air balloon. It was found that the rate constant of CeR/CN-66% was 3 times as high as that of pure CeO2 or g-C3N4. All kinds of structural characterizations suggested the formation of heterojunction between the CeO2 and g-C3N4, serving as a tunnel for the transfer of photoinduced charge, which may contribute to the improvement of photoactivity. Moreover, the Ce3+ ions and oxygen vacancy significantly promoted the adsorption and activation of substrate or molecular O2. Therefore, the efficient separation of the charges, the prolonged photoinduced electron lifetime, and the abundant defect structure (increased content of Ce3+ ions or the oxygen vacancy) were considered as the main factors for the higher photo-oxidation efficiency of the CeR/CN-66%. Another striking observation that was noticed was that the CeR/CN-66% was recycled up to five cycles under the same condition and was found to be highly efficient without any obvious decrease in the activity or selectivity due to the outstanding stability of the defect structure. Thus, highly efficient CeR/CN-x heterojunction catalyst was synthesized in this work by a simple approach for the photo-oxidation of benzylamine under mild reaction conditions, and this finding may provide wide applications in other photocatalysis areas.
研究领域:
催化化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2020
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IF 16.683
Peng Kong,Hao Tan,Tingyu Lei,Jie Wang,Wenjun Yan,Ruiyi Wang,Eric R. Waclawik,Zhanfeng Zheng,Zhong Li
Conjugated polyimide (R-PI) containing triazine ring was synthesized by a modified thermal solid-state polymerization of the salt monomer. The structure of the as-prepared R-PI was characterized by FTIR, XPS, EPR, EA and solid-state 13 C NMR, which is rich in oxygen vacancies (OVs). The R-PI exhibits excellent catalytic performance for selective benzylamine oxidation reactions under visible light. Both experimental and theoretical calculation results indicated that the introduction of OVs could increase the level of electron delocalization of R-PI. R-PI possess more excitable electrons and a narrower band gap, which expands the absorption of long-wavelength light. The surface OVs also serve as excellent sites for molecular O 2 adsorption and activation. Chemisorbed O 2 spatially builds up a channel for the delivery of photoexcited electrons to O 2 , which effectively enhanced separation efficiency of photogenerated charge carriers. These results indicate that OVs-rich conjugated polyimides can be efficient visible light-responsive photocatalysts for green synthesis.
研究领域:
材料科学
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光催化化学
✓ 已验证
DOI
高影响因子
Journal of Nanomaterials
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2021
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IF 2.986
Yangxu Luo,Juan Du,Huadi Xiao,Ling Zheng,Xuncai Chen,Ande Ma,Qizhi Luo
Accurate identification and quantification of methamphetamine (MA) and its related substances are essential for the investigation and fair trial of drug offenses. In this study, a modified LC-ESI-MS/MS method for the simultaneous determination of MA and its isomer N-isopropylbenzylamine (N-IBA) in forensic samples was developed and validated. Optimum chromatographic separation of the target analytes was achieved on an Agilent Poroshell 120 SB-C18 column ( mm, 2.7 μm) at 40°C with isocratic elution at the flow rate of 0.40 mL/min. The mobile phase was acetonitrile and 20 mM ammonium acetate solution containing 0.1% formic acid (80 : 20, ). Positive ESI-MS/MS detection was performed in multiple reaction monitoring (MRM) mode to identify and quantify the target analytes. Method validation showed excellent linearity in the range of 0.51 ng/mL~51 ng/mL for MA and N-IBA. The low limit of detection (LLOD) and low limit of quantification (LLOQ) reached 0.1 ng/mL and 0.3 ng/mL for both analytes. The method showed a satisfactory accuracy with an inter- and intraday-relative error (RE) <20%, and a precision of inter- and intraday relative standard deviation (RSD) less than 15%. The validated method was successfully applied in real forensic samples and resulted in the detection of MA and N-IBA in 8 suspected samples in drug cases that only deemed MA positive using our previous routine screening procedure, which avoided the misidentification of N-IBA as MA.
研究领域:
分析化学
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法医学
✓ 已验证
产品关联
DOI
高影响因子
Molecular Catalysis
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2024
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IF 3.9
Fangfang Huang,Xinyin Zhang,Yuhong Chang,Wenwen Chen,Haishun Wu,Lei Li,Jianfeng Jia
Semiconductor photocatalytic organic reactions have garnered extensive interest owing to their environmentally friendly and sustainable advantages. Herein, the preparation of Ag 2 S@CdS p-n heterojunction through in-situ ion exchange reaction for photocatalytic benzylamine coupling is reported. Compared with pure CdS, Ag 2 S@CdS exhibited significantly enhanced photocatalytic activity for the oxidative coupling reaction of benzylamine. In particular, Ag 2 S@CdS showed high photocatalytic benzylamine conversion (>99 %) after 90 min under sunlight irradiation. The photocatalytic performance test at different wavelengths shows that the broadening of the light absorption range of Ag 2 S@CdS effectively improves the utilization of visible light. The photoelectric performance test demonstrates that the internal electric field of the p-n heterojunction effectively enhances the efficiency of separating photogenerated carriers. Moreover, Ag 2 S@CdS exhibited excellent compatibility with various benzylamine derivatives. The mechanism of photocatalytic benzylamine oxidation by Ag 2 S@CdS was investigated. This work provides some insights into the design of visible-light photocatalysts for selective organic synthesis.
研究领域:
材料科学
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有机合成
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光催化
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
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2025
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IF 6.5
Weidong Liu,Jianguo Liu
Benzylamine production from the hydrogenation of nitrile is attractive, but most of the catalysts are complicated and costly. In this paper, a simple synthesis of self-nitrogen-doped carbon-supported nickel biobased sustainable catalyst (Ni-JKS-600) for benzylamine hydrogenation with benzonitrile has been reported. The catalyst has high specific surface area, abundant micro-mesoporous structure and nickel hydrogenation active site. By optimizing the reaction conditions, a mild reaction condition (120 ℃, 2 MPa H 2 , 3 h) was determined, and it was found that the solvent had a significant effect on the selectivity of benzylamine, and the selectivity of benzylamine could reach 97.08 % when ammonia methanol was used as the solvent. Ni-JKS-600 catalyst is superior to precious metal catalysts (Ru, Pt, Ir, Pd) in aniline selectivity, and is comparable to Raney nickel catalyst, which shows its potential application in industrial production of amines. The catalyst uses cheap and widely available chitin as carbon and nitrogen source, and has the characteristics of green economy with simple preparation method and low cost. It is expected to replace precious metal catalyst for efficient production of benzylamine in the future.
研究领域:
催化化学
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绿色化学
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产品关联
DOI
高影响因子
ANALYTICAL LETTERS
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2024
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IF 1.6
Zekun Tang,Huihui Wan,Huaishuan Zhang,Yu Zhang,Min Ju,Jinfeng Zhao,Yuming Sun,Lina Zhou,Qingxin Yin,Rui Cai,Qiang Xu,Yuming Song,Hua Zhang
As an important circulating metabolite in the body, the accurate determination of glucose in body fluids is very important for the evaluation of physiological status. However, liquid chromatography–mass spectrometry (LC–MS) methods present challenges for glucose due to poor ionization combined with weak chromatographic retention. Here, a method for determining salivary glucose using LC–MS after derivation by dibenzylamine is described in which 3-O-methyl-D-glucopyranose was used as internal standard. Saliva samples were prepared by protein precipitation, and the analytes were separated on a polar-copolymerized C18 reversed phase column. Detection took place by high-resolution orbitrap mass spectrometry after ionization in the positive mode. The calibration function was linear from 0.35 to 50 ng/mL. The recoveries were from 97.82 to 104.51% for intraday assays and 98.96 to 106.61% for interday assays. The intraday precision of salivary glucose was from 0.37% to 1.43% and the interday precision from 1.33% to 1.43%. The limits of detection and quantification in saliva were 0.2 and 0.6 ng/mL. The samples after derivatization were stored at 4 °C and 25 °C and analyzed every two days with five repeats. The relative standard deviations were 0.09% and 0.27% at 4 °C and 25 °C. This method was employed for the determination of the glucose in saliva for healthy male college students after exercise.
研究领域:
分析化学
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医学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
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2022
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IF 10.383
Qian-Qian Chu,Zhijian Sun,Yan Liu,Hao Cui,Bo Cheng,Davoud Dastan,Kyoung-sik Moon,Guan-Jun Yang,Ching-Ping Wong
As one of the most competitive light-harvesting materials, organometal halide perovskites have attracted great attention due to their low-cost and top-down solution fabricability. However, the instability of perovskites in a moist environment reduces the potential for their commercialization. In this study, novel 2,4-fluorobenzylamine (FBA) was employed as the passivation material, which could successfully suppress the defects and improve the moisture resistance of perovskites, resulting in an ultrahigh power conversion efficiency of 17.6% for the carbon-based perovskite solar cells with good stability. Meanwhile, the whole process of interactions between the H2O molecule and the perovskite lattice was first elucidated by density functional theory calculations, which demonstrated the underlying mechanism of the improvement of moisture stability with the FBA treatment. This work opens up a new route toward addressing the main obstacles in the practical application of perovskite devices under ambient conditions.
研究领域:
材料科学
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能源技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED ORGANOMETALLIC CHEMISTRY
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2024
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IF 3.7
Lifei Liu,Xiaoqing Yang,Pengfei Li,Luyuan Zhang,Yali Luo,Meng Yan,Yang Deng,Xia An,Jianling Zhang,Xu Wu
The construction of metal–organic frameworks (MOFs) with desirable structures for high-performance photocatalysis is attractive but remains challenging. Here, a hierarchically meso- and microporous sc Cu-MOF-74 was synthesized in supercritical CO 2 ( sc CO 2 )/methanol solution. Compared with the conventional microporous Cu-MOF-74, the meso- and microporous sc Cu-MOF-74 has more exposed and accessible Lewis acid sites derived from the missing-linker defects. The unique structure endows sc Cu-MOF-74 with superior molecular accessibility, enhanced separation, and transfer efficiency of photogenerated charges. High catalytic activity and reusability can be achieved in photo-oxidative coupling of amines, reaching a maximum N-benzylbenzaldimine yield rate of 4.80 mmol g −1 h −1 under mild conditions, that is, air atmosphere and room temperature. This study provides a new idea for improving the intrinsic photocatalytic activities of MOFs.
研究领域:
材料科学
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化学工程
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催化
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）