ACS Sustainable Chemistry & Engineering
·
2021
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IF 8.198
Jianyi Lei,Jiajun Dai,Kok Bing Tan,Jiale Huang,Guowu Zhan,Qingbiao Li
Direct epoxidation of propylene to propylene oxide (PO) with molecular oxygen as the most atomically economical route remains challenging due to the low PO yield. In this study, CuO supported on perovskites (LaCoO3) modified with NaCl was found to be active for direct epoxidation of propylene with oxygen. LaCoxCu1–xO3– modified with alkali metal salts were further fabricated to improve catalytic performance with the assistance of citric acid. Among the investigated catalysts, LaCo0.8Cu0.2O3−δ exhibited the best catalytic performance, with a PO formation rate of 60.4 gPO·kgcat−1·h−1 (PO selectivity of 10.2% and propylene conversion of 12.0%) at a lower temperature (250 °C). The characterization results indicate that Cu-doped LaCoO3 catalysts with enhanced oxygen vacancies and abundant electrophilic oxygen species are crucial to selectively attack on C═C bond instead of C–H bond. Besides, LaCoxCu1–xO3−δ catalysts demonstrated higher propylene conversion and more stable catalytic performance. This work exemplifies the direct propylene epoxidation with molecular oxygen employing perovskite materials.
研究领域:
催化化学
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材料科学
✓ 已验证
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2024
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IF 2.7
Hengxi Wang,Xiaonan Yang,Lijun Meng,Senjian Han,Shiqiang Wang,Yafei Guo,Tianlong Deng
Prussian blue analogue (PBA) membranes for efficient Cs removal via in situ synthesis have attracted much interest. Herein, copper-substituted PBA was developed and optimized on the surface of a substrate with the aid of tannic acid (TA). The fabricated Cu-PBA-TA membrane was systematically investigated for its Cs adsorption property in static and dynamic experiments. The as-prepared membrane showed a maximum adsorption capacity of 265.0 mg g−1, which was the highest when compared to that of previously reported PBA membranes. Applied in geothermal water, the Cu-PBA-TA membrane showed favorable selectivity (Kd, 8680 mL g−1) and the removal rate of Cs+ was about 90%. Its fast adsorption rate that reached equilibrium within 40 min and the benign reusability in the dynamic treatment of geothermal water confirmed the potential of the membrane for large-scale application.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ELECTRONIC MATERIALS
·
2024
·Vol. 53
·期 12
·7380-7389
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IF 2.2
Qian Qingyang,Cui Menglin,Xu Hongyu,Chen Tingting,Liu Juntao,Zhu Xiaohui,Xu Jing,Xia Hui
P3-type K 0.45 Mn 0.8 Cu 0.2 O 2 and K 0.45 MnO 2 layered oxides were prepared and studied as cathode materials for sodium-ion batteries. The impact of Cu substitution for Mn and the electrochemical performance of both samples were comprehensively investigated. Of particular interest is the P3-type K 0.45 Mn 0.8 Cu 0.2 O 2 , which exhibited enhanced diffusion capability and improved structural stability, resulting in an impressive reversible capacity of 109 mAh g −1 at 20 mA g −1 within the voltage range of 1.5–4.0 V (Na + /Na), superior rate capability of 74 mAh g −1 at 500 mA g −1 , and excellent cycling performance with 86% capacity retention after 150 cycles at 20 mA g −1 . The substitution of Cu for Mn effectively mitigates Na + /vacancy ordering and complex phase transition observed in P3-K 0.45 MnO 2 . Post-cycling phase characterization indicates the presence of excess K ions in the layers, contributing to the stabilization of the layered structure. This previously unreported class of P3 cathode material introduces new perspectives for the advancement of layered cathode materials for high-performance and cost-effective sodium-ion batteries. Graphical
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2019
·
IF 7.65
Ruixin Yu,Jianhui Zhao,Zhiwei Zhao,Fuyi Cui
In this paper, copper substituted zinc ferrite (ZCFO) catalyst with rich oxygen vacancies (OVs) was synthesized via a simple one pot sol-gel combustion method, and firstly used for peroxymonosulfate (PMS) activation to degrade a typical antibiotic ciprofloxacin (CIP). Only ∼15 min was required to achieve 96.6% of CIP degradation using ZCFO as the catalyst, and the pseudo-first-order reaction constant was about 95 times higher than that of conventional zinc ferrite (1.90 min −1 vs 0.02 min −1 ). ZCFO catalyst showed great stability and reusability based on the successive degradation cycles and could be easily recovered through magnetic separation. Besides, the effects of catalyst loading, PMS concentration, reaction temperature, initial solution pH, coexisting anions and humic acid (HA) on CIP degradation were systematically investigated. Radical quenching tests and electron paramagnetic resonance (EPR) revealed that sulfate radical ( SO 4 -. ), hydroxyl radical ( OH∙ ), superoxide radical ( O 2 ∙- ) and singlet oxygen ( 1 O 2 ) were involved in the ZCFO/PMS system, among which O 2 ∙- and 1 O 2 were the dominant reactive oxygen species (ROS). The excellent catalytic activity of ZCFO was ascribed to the dual active sites of Fe and Cu and large amount of OVs after Cu substitution, which was beneficial to generate ROS for CIP removal.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Min Yang,Yong Zheng,Weimin Ding,Xuepeng Lu,Zhiyi Jiang,Bo Li,Zuowei Dong,Wei Zhou
To explore high-performance dielectric ceramics with intrinsically low sintering temperatures and low permittivity suitable for use in the microwave (MW) and terahertz (THz) ranges, Cu ions were selected to replace Zn ions in BaZnP 2 O 7 ceramics based on the considerations of ionic radius and chemical bond characteristics. Samples with moderate Cu 2+ substitution exhibited better performance than conventional ones, with a similar dielectric mechanism in both MW and THz frequency ranges. All samples of BaZn 1- x Cu x P 2 O 7 (0 ≤ x ≤ 0.1) solid solutions exhibit a single-phase with a triclinic structure ( P-1 ) when the sintering temperature is below 925 °C, while the BaCuP 2 O 7 phases form in the doped samples at 925 °C. Cu 2+ substitution improves density and enhances molecular polarizabilities and average ionicity, thereby raising the dielectric constant ε r . The substitution of Cu 2+ for Zn 2+ in BaZnP 2 O 7 ceramics shortens the chemical bonds, thus improving lattice stability and reducing the damping factor of phonon anharmonic vibrations. This, in turn, increases the Q × f values by 1.65 times and enhances temperature stability compared to conventional ceramics. The BaZn 1- x Cu x P 2 O 7 ceramics have good chemical compatibility with Cu, but react with Ag.
研究领域:
材料科学
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陶瓷
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介电材料
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固体物理
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微波技术
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太赫兹技术
✓ 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）