Article
Chemistry, Multidisciplinary
Hongfei Ma, Xiuhui Zheng, Hao Zhang, Guoyan Ma, Wei Zhang, Zheng Jiang, De Chen
Summary: Fine reconstructing the chemical environment of Cu-N-C SAC with Cu-P moiety modulation achieves superior performance in ethylene oxychlorination. The Cu-NPC catalyst exhibits Cu site activity four times higher than P-free Cu-NC catalyst and 25 times higher than Ce-promoted CuCl2/Al2O3 catalyst. The fine construction with another heteroatom provides a theoretical framework for catalyzing ethylene oxychlorination and expands the application of carbon-based SACs in heterogeneous catalysis.
Article
Chemistry, Physical
Wei Zhang, Hongfei Ma, Yalan Wang, Samuel Konrad Regli, Magnus Ronning, Kumar Ranjan Rout, Tigran Margossian, De Chen
Summary: The oxidation state of Cu species in ethylene oxychlorination is closely related to its catalytic performance. CuCl2 and CuCl are the primary active sites in the reduction and oxidation steps, respectively. The distribution of active sites is determined by the kinetic equilibrium of reduction, oxidation, and hydrochlorination rates. In this study, in situ X-ray absorption spectroscopy (XAS) and operando UV-vis-NIR spectroscopy were used to study the dynamic changes of Cu active sites in La-doped CuCl2/c-Al2O3 catalysts. A higher CuCl2 concentration significantly improves the activity, EDC selectivity, and stability. The presence of La enhances the reducibility of CuCl2 and modifies the catalytic performance rather than directly participating in the redox cycle. This study provides a deeper understanding of the role of active species and promoters in CuCl2/c-Al2O3 catalysts for ethylene oxychlorination.
JOURNAL OF CATALYSIS
(2023)
Article
Engineering, Environmental
Hongfei Ma, Erling S. Sollund, Wei Zhang, Endre Fenes, Yanying Qi, Yalan Wang, Kumar R. Rout, Terje Fuglerud, Marco Piccinini, De Chen
Summary: A kinetic model considering the dynamic nature of active sites in Mars-van Krevelen type reactions was developed to predict the evolution of reactant and product composition, as well as CuCl2 concentration in the solid catalyst. By combining transient and steady-state kinetic modeling, the model successfully described the transient response of reduction and oxidation steps, as well as the reaction at steady state under different conditions, providing a better understanding of Mars-van Krevelen type reactions.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Engineering, Environmental
Wei Zhang, Endre Fenes, Hongfei Ma, Erling Olav Sollund, Tigran Margossian, Kumar Ranjan Rout, De Chen
Summary: This study investigates the effects of 14 metal chlorides on the CuCl2/gamma-Al2O3-based catalysts used for ethylene oxychlorination. The results show that promoter doping can tune the redox behavior of the catalysts and the impact on the reaction rate and CuCl2 concentration varies with different promoters.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Chemistry, Physical
Mikalai A. Artsiusheuski, Jeroen A. van Bokhoven, Vitaly L. Sushkevich
Summary: The one-step valorization of natural gas is still a challenge, and converting methane to methanol via chemical looping over copper-containing zeolites seems to be a promising route. CuMFI is one of the earliest successful methods, but the structure of the active sites in CuMFI and the influence of copper loading and Si/Al ratio on the copper speciation are still not well understood. It has been found that the Cu/Al ratio determines the selectivity of methane conversion in CuMFI by controlling the structure of the active dicopper sites.
Article
Chemistry, Physical
Mikalai A. Artsiusheuski, Jeroen A. van Bokhoven, Vitaly L. Sushkevich
Summary: The one-step valorization of natural gas is a challenge, and converting methane to methanol via chemical looping over copper-containing zeolites shows promise. Research has found that the Cu/Al ratio determines the selectivity of methane conversion by controlling the structure of the active copper sites.
Article
Chemistry, Physical
Natthapong Monarumit, Thanapong Lhuaamporn, Pornsawat Wathanakul, Chatree Saiyasombat, Wiwat Wongkokua
Summary: Recently, the concept of Fe3+-Ti4+ mixed acceptor states in the energy band gap of sapphire has been proposed as the cause of blue coloration. The blue color in sapphire is faded and turns yellow by beryllium heat treatment. It has been revealed as the color center in Be-treated yellow sapphires. The mechanism underlying these phenomena was explained and discussed in this study.
RADIATION PHYSICS AND CHEMISTRY
(2023)
Article
Food Science & Technology
Gema Puertas, Patricia Cazon, Manuel Vazquez
Summary: Membrane separation technology is widely used in research, food and pharmaceutical industries. This study assessed the application of UV-VIS-NIR spectroscopy in quantifying the composition of fractions obtained through membrane separation. The results showed that UV-VIS-NIR spectroscopy combined with chemometric tools is a reliable and efficient method for composition analysis in the membrane filtration process.
LWT-FOOD SCIENCE AND TECHNOLOGY
(2023)
Article
Chemistry, Physical
Alessandro Piovano, Matteo Signorile, Luca Braglia, Piero Torelli, Andrea Martini, Toru Wada, Gentoku Takasao, Toshiaki Taniike, Elena Groppo
Summary: Although Ziegler-Natta (ZN) catalysts are crucial in the polyolefin market, a comprehensive understanding of their properties at the molecular level is still lacking. This study uses UV-vis and Ti L-2,L-3-edge near-edge X-ray absorption fine structure (NEXAFS) spectroscopies, along with theoretical simulations, to investigate the electronic properties of three ZN precatalysts and their corresponding catalysts activated by triethylaluminum (TEAl). The research provides evidence for the presence of monomeric 6-fold-coordinated Ti4+ species in all precatalysts, sheds light on the correlation between Ti site electron density and olefin insertion activation energy, and demonstrates the impact of effective charge on the Ti sites on olefin pi-complexation.
Article
Spectroscopy
Vlasta Mohacek-Grosev, Sandro Brljafa, Marko Skrabic, Ivan Maric, Vesna Blazek Bregovic, Vincenzo Amendola, Polona Ropret, Anita Kvacek Blazevic
Summary: The study investigated the binding of glucosamine to colloidal gold nanoparticles through various techniques including SERS, DLS, and UV-VIS spectroscopy. The results showed that the addition of glucosamine led to an increase in both the size and hydrodynamic diameter of the gold nanoparticles, with different concentrations of glucosamine displaying distinct Raman peaks.
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2022)
Article
Horticulture
Kusumiyati Kusumiyati, Ine Elisa Putri, Jajang Sauman Hamdani, Diding Suhandy
Summary: This study investigated the potential application of visible/near-infrared (Vis/NIR) spectroscopy in quantitative detection of nutritional compounds in green 'Ratuni UNPAD' cayenne pepper. The experimental results showed that Vis/NIR spectroscopy had good model indicators for total carotenoids, water content, and capsaicin parameters.
Article
Engineering, Environmental
Yangzi Shangguan, Renji Zheng, Qiuyue Ge, Xuezhen Feng, Ranhao Wang, Yuanhao Zhou, Siyuan Luo, Lele Duan, Jia Lin, Hong Chen
Summary: The research demonstrates that platinum decoration based on interfacial engineering can effectively enhance the photocatalytic efficiency of semiconductor photocatalysts by modulating band structure and accelerating interfacial reaction dynamics. The Pt/CuFeS2 QDs show improved light absorption capability and faster charge transfer efficiency, leading to a three-fold increase in photocatalytic Cr(VI) reduction efficiency compared to original CuFeS2 QDs.
JOURNAL OF HAZARDOUS MATERIALS
(2022)
Article
Engineering, Electrical & Electronic
C. J. Keerthi, Sayan Halder, Sohel Siraj, Chanchal Chakraborty, Parikshit Sahatiya, Subhradeep Pal
Summary: In this letter, we present a MoSSe-based wideband photodetector (PD) synthesized hydrothermally, which exhibits excellent responsivity and sub-second response time. The device structure consists of MXene/MoSSe/Ag on a Si substrate, with MXene (Ti(3)C(2)Tx) and Ag serving as the cathode and anode contact of the PD, respectively. The Ti(3)C(2)Tx and MoSSe layers are deposited using the spin-coating method, while the Ag electrode is deposited through thermal evaporation. The fabricated PD shows outstanding photodetection capability from 350 nm to 950 nm, with a peak responsivity of 8.89 A.W-1 at 460 nm. The measured external quantum efficiency (EQE) and detectivity (D*) at 420 nm are 24.96% and 9.07 x 10(9) Jones, respectively. Additionally, the PD demonstrates good linearity performance up to 343 K, and the rise and fall times are approximately 0.12 sec and 0.13 sec, respectively.
IEEE PHOTONICS TECHNOLOGY LETTERS
(2023)
Article
Materials Science, Multidisciplinary
Guangqiang He, Zhihui Xiong, Hui Yang, Ming Yang, Zhixi Li, Tixian Zeng, Xinyou An, Min Zhang
Summary: Cadmium chalcogenide thin films (CdSe0.2Te0.8) were successfully deposited on glass substrates by radio frequency magnetron sputtering, exhibiting a cubic zinc-blende structure with no secondary phases. The band gap of CdSe0.2Te0.8 varied slightly with film thickness in the range of 1.41-1.43 eV, making them potentially suitable for use as a photovoltaic absorption layer in ultra-thin solar cells.
Review
Instruments & Instrumentation
Xuan Qi, Yudong Lian, Luyang Xie, Yulei Wang, Zhiwei Lu
Summary: Water pollution poses a significant threat to public health and social stability due to rapid economic development and urbanization. Therefore, accurate and rapid monitoring of water quality is crucial. Spectral analysis technology, as an environmentally friendly, nondestructive, and efficient detection technology, provides an effective tool for qualitative analysis and quantitative detection of pollutants in the water environment. This paper studies the principles of UV-Vis spectroscopy and near-infrared (NIR) spectroscopy and their applications in water quality detection. It discusses the use of UV-Vis and NIR spectroscopy techniques for detecting various water quality parameters.
APPLIED SPECTROSCOPY REVIEWS
(2023)
Article
Chemistry, Multidisciplinary
Dong Lin, Quande Zhang, Zhengxing Qin, Qing Li, Xiang Feng, Zhaoning Song, Zhenping Cai, Yibin Liu, Xiaobo Chen, De Chen, Svetlana Mintova, Chaohe Yang
Summary: The green and efficient synthesis of titanium-containing molecular sieves is hindered by environmentally unfriendly additives and complicated procedures. A new additive-free route has been developed using hydroxyl free radicals generated from ultraviolet irradiation, successfully reversing the formation of titanium oligomers to match hydrolysis rates of titanium and silicon species. This approach shows fantastic catalytic performance for propene epoxidation with H-2 and O-2, opening up new opportunities for high-efficiency, environmentally friendly, and facile production of pure titanium-containing molecular sieves compared to conventional hydrothermal methods.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Can Li, Xiaobo Chen, Lihua Zhang, Shaohui Yan, Anju Sharma, Bo Zhao, Amar Kumbhar, Guangwen Zhou, Jiye Fang
Summary: The study successfully prepared octahedral CuNi@Pt-Cu core@shell nanocrystals using a colloidal seed-mediated method, achieving uniform Pt-based shells with a thickness of less than 1 nm by precisely controlling synthesis conditions. The resulting nano-octahedra exhibited superior activity in electrochemical methanol oxidation reaction compared to commercial Pt/C catalysts and nano-polyhedron counterparts of CuNi@Pt-Cu.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Muhammad Zeeshan, Qing-Yu Chang, Jun Zhang, Ping Hu, Zhi-Jun Sui, Xing-Gui Zhou, De Chen, Yi-An Zhu
Summary: The catalytic properties of CeO2 catalyst for propane dehydrogenation were studied using density functional theory calculations, revealing a considerable Lewis acid-base interaction on the defective surfaces that enhances bond formation between adsorbates and the catalyst surface, resulting in increased surface reactivity.
CHINESE JOURNAL OF CHEMISTRY
(2021)
Article
Chemistry, Physical
Xiaoli Yang, Jia Yang, Yalan Wang, Tao Zhao, Haoxi Ben, Xuning Li, Anders Holmen, Yanqiang Huang, De Chen
Summary: The Na and S-modulated FeMnOx catalysts play a crucial role in enhancing CO conversion, promoting olefin formation, and suppressing methane generation in Fischer-Tropsch synthesis of light olefins. Multiple characterizations and kinetic analysis confirmed that the promoters increase the formation of active species and lower CO activation energy. The study provides a practical strategy for developing highly active and stable FTO catalysts.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2022)
Article
Chemistry, Multidisciplinary
Jonas Van Belleghem, Jia Yang, Pieter Janssens, Jeroen Poissonnier, De Chen, Guy B. Marin, Joris W. Thybaut
Summary: An extended Single-Event MicroKinetic (SEMK) model successfully simulated Steady State Isotopic Transient Kinetic Analysis (SSITKA) data for Co catalyzed Fischer-Tropsch Synthesis (FTS), providing meaningful estimates for activation energies and atomic chemisorption enthalpies. The model analysis revealed the nature of two site types and the reaction preference for CO on step sites, as well as the role of terrace sites in methane production and alkane hydrogenation. The metal particle size effect was attributed to the increasing importance of terrace sites on reaction kinetics.
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
(2022)
Article
Chemistry, Physical
Jie Yang, Erlend Bjorgum, Hui Chang, Ka-Ke Zhu, Zhi-Jun Sui, Xing-Gui Zhou, Anders Holmen, Yi-An Zhu, De Chen
Summary: Research has shown that the dynamic nature of active sites on La-Fe-based perovskites in chemical looping methane oxidation is influenced by the Fe coordination environment (and hence the oxygen vacancy concentration), which is the key parameter governing the catalyst selectivity.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2022)
Article
Thermodynamics
Xin Zhou, Shangfeng Li, Yuan Wang, Jiewenjing Zhang, Zhibo Zhang, Changgui Wu, Xiaobo Chen, Xiang Feng, Yibin Liu, Hui Zhao, Hao Yan, Chaohe Yang
Summary: The study introduced a novel hierarchical catalytic cracking process for crude oil, leading to increased conversion rate and olefin yields. Optimization of key operating parameters improved hydrogen and carbon atoms efficiency, net present value, and internal rate of return. Additionally, the novel process reduced greenhouse gas emissions, wastewater generation, and non-renewable energy consumption compared to conventional processes.
ENERGY CONVERSION AND MANAGEMENT
(2022)
Article
Materials Science, Multidisciplinary
Xiukuang Zhang, Jie Yin, Qian Lei, Xiangpeng Meng, Xiaobo Chen, Zhou Li
Summary: The study showed that high-throughput fabrication using directed energy deposition allowed for rapid production of gradient Cu-Fe-Cr alloys, with liquid diffusion and decomposition precipitation contributing to gradient variation in microstructure and composition, leading to increased hardness. Machine learning was successfully employed to predict alloy hardness, aiding in the acceleration of alloy design and fabrication.
Article
Optics
Xiao Yang, Xiaobo Chen, Juntong Xi
Summary: This work presents an efficient initial value estimation method for speckle control points matching using digital image correlation (DIC) based on perspective transformation. The proposed method achieves higher calibration accuracy compared to regular planar chessboard or circular marker array calibration targets, as well as higher measurement precision compared to the speckle pattern calibration method that uses SIFT-based initial value estimation.
Article
Chemistry, Multidisciplinary
Haitao Zhou, Chongchen Yu, Hongquan Gao, Jian-Chun Wu, Dong Hou, Menghao Liu, Minghui Zhang, Zifu Xu, Jianhong Yang, De Chen
Summary: The study introduces a solid state separator made of lithiated polyphenylene sulfide and functionalized to improve Li+ transference, allowing lithium metal batteries to achieve higher energy and power densities under high loadings and voltages.
Article
Chemistry, Physical
Qing Lu, Chen Chen, Qian Di, Wanli Liu, Xiaohui Sun, Yongxiao Tuo, Yan Zhou, Yuan Pan, Xiang Feng, Lina Li, De Chen, Jun Zhang
Summary: Efficient and stable electrocatalysts are crucial for the electrocatalytic CO2 reduction reaction (CO2RR) into chemical products. In this study, a NC@Ni/C nano-composite with a core-shell structure was developed as an effective electrocatalyst for CO2RR to CO over a wide potential range. The catalyst exhibited high CO Faradaic efficiency and excellent stability, primarily attributed to the pyridinic-N doping in the carbon shell of Ni NPs.
Article
Engineering, Environmental
Jithin Gopakumar, Pal Martin Benum, Ingeborg-Helene Svenum, Bjorn Christian Enger, David Waller, Magnus Ronning
Summary: This study summarizes the use of a gamma-Al2O3 supported Ru catalyst for the oxidation of NO to NO2 in industrial nitric acid production. The catalyst exhibited high activity and kinetic parameters under nitric acid plant conditions, and the apparent activation energy and reaction mechanism were investigated.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Chemistry, Physical
Jithin Gopakumar, Sunniva Vold, Bjorn Christian Enger, David Waller, Per Erik Vullum, Magnus Ronning
Summary: The Ostwald process is the most common industrial process for producing nitric acid. This research focuses on catalytic oxidation of NO to NO2 using silver-promoted manganese on zirconia catalysts under industrially relevant conditions. The results show that the manganese catalysts can work effectively at low temperatures and concentrations relevant to industrial catalytic oxidation of NO.
CATALYSIS SCIENCE & TECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
Bao Zhao, Xiaobo Chen, Xinyi Le, Juntong Xi, Zhaohong Jia
Summary: This article evaluates thirteen popular transformation estimation proposals on both descriptor-based and synthetic correspondences, comparing their accuracy, robustness, and efficiency performance. The results provide valuable findings that may supplement existing evaluations of transformation estimation techniques.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2021)
