FUEL
·
2018
·
IF 4.908
Zihao Zhang,Hao Chen,Changxue Wang,Kequan Chen,Xiuyang Lu,Pingkai Ouyang,Jie Fu
In this work, a series of ZrO 2 -supported Cu, Ni and bimetallic Cu-Ni catalysts were synthesized and evaluated for their activity and stability in the in situ hydrogenation and decarboxylation of oleic acid using methanol as a hydrogen donor. High-angle annular dark-field scanning transmission electron microscopy (HADDF-STEM), energy dispersive X-ray spectroscopy (EDS-mapping), X-ray diffraction (XRD) and temperature programmed reduction (TPR) characterizations revealed that the as-synthesized Cu-Ni/ZrO 2 was a Cu-Ni alloy that was highly dispersed on mixed m-ZrO 2 and t-ZrO 2 . The bimetallic Cu-Ni/ZrO 2 nanostructures not only exhibited better catalytic activity for the conversion of oleic acid compared to monometallic Cu/ZrO 2 and Ni/ZrO 2 catalysts but also demonstrated good reuse performance. The formation of the Cu-Ni alloy facilitated the decarboxylation reaction and inhibited the cracking reaction, leading to enhanced catalytic performance. The good stability of Cu-Ni/ZrO 2 was primarily due to the good hydrothermal stability of the ZrO 2 support.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2025
·
IF 3.9
Lei Wu,Xiuyun Ma,Xiumei Liu,Hong Du,Feng Wang
Hydrogenation of xylose is an important industrial process for the production of xylitol, which is known as a healthy sweetener. In this work, bimetallic phyllosilicate-derived Cu–Ni alloy catalysts were constructed via an ammonia evaporation method followed by reduction under hydrogen and applied for the hydrogenation of a high-concentration xylose aqueous solution for the production of xylitol. The Cu–Ni alloy catalysts exhibited higher xylose conversion than the corresponding monometallic Cu and Ni catalyst. And the xylitol yield was increased with the increase of the ratio of nickel to copper for the bimetallic alloy catalyst. The higher xylose conversion was obtained at elevated reaction temperature and H2 pressure. In addition, reduction conditions, especially temperature, were found to significantly influence the catalytic activity of the phyllosilicate-derived Cu–Ni alloy sample. The 5Cu15Ni-EA catalyst activated at 700 °C exhibited excellent performance for xylose hydrogenation in terms of xylose conversion (>99%) and xylitol selectivity (>99%) under moderate conditions (100 °C and 4 MPa H2). The performance of the 5Cu15Ni-EA catalyst is also superior to the reported consequences of xylitol manufacture via hydrogenation over a Raney nickel catalyst and a co-impregnation-derived bimetallic catalyst. Furthermore, the xylitol yield did not change obviously for 5Cu15Ni-EA during the 200 h of continuous reaction in a fixed bed reactor. The XRD, XPS, HRTEM–EDS mapping, and line scan results of the fresh reduced 5Cu15Ni-EA sample verified the existence of a highly dispersed Cu–Ni alloy. The formation of these uniformly dispersed Cu–Ni alloy sites induced efficient performance for the hydrogenation of a high-concentration xylose aqueous solution.
研究领域:
化学工程
·
催化材料科学
✓ 已验证
产品关联
DOI
高影响因子
ChemCatChem
·
2021
·Vol. 13
·期 19
·4164-4181
·
IF 5.686
Qiuli Fu,Shibo Yang,Ping Ning,Rongrong Miao,Liang He,Qingqing Guan
Graphical Selective hydrogenation : In rubber seed shell porous biochar supported Cu−Ni bimetals, the formed Cu 1 Ni 3 alloy stabilized the excessive Cu species which were in the lattice on the inner/outer surfaces of the rss AC support. The catalytic activity is retained, ensuring that the catalyst would neither be oxidized nor aggregated severely. The prepared high-efficiency Cu 1 Ni 1 / rss AC catalyst catalyzed the hydrogenation reaction of FAL to produce FOL, THFA and 2-MF. Using cheap Cu-based catalysts for highly selective hydrogenation of furfural (FAL) is of great importance of upgrading this biomass-derived platform molecule but is still challenging for large-scale application due to the low conversion efficiency and the easy aggregation of Cu active sites. To address these issues, a nitrogen-autodoped porous biochar derived from rubber seed shell ( rss AC) was fabricated for anchoring Cu sites on a nanoscale. Moreover, by the co-crystallization strategy of Cu and the second metal (M, M=Ni, Zn, Co, Ce), stable Cu−M nanoalloys were constructed on the surface of the rss AC support. The FAL hydrogenation experiments showed that the type, proportion and loading amount of the second metal had great effect on the catalytic efficiency. Compared with the other metals, Ni-doped Cu/ rss AC catalyst exhibited the best hydrogenation performance due to their extraordinary adsorption and activation capacity for hydrogen. Further, the highest catalytic efficiency was observed using 20 % Cu 1 Ni 1 /rss AC catalyst. The characterization results showed that the key to its success was highly-dispersive anchoring of the CuNi active sites onto the inner/outer surface of the nanopores of rss AC support by the strong interaction between the surface N-containing functional groups and metals. Of note, the formed CuNi alloys with the Cu/Ni atomic ratio of 1 : 3 played an important role in the stabilization of the adjacent nano-dot matrix Cu 0 species. Kinetic test indicated that the formation step of furfuryl alcohol (FOL) from FAL was still the key step and the hydrogenation products can be converted between FOL and tetrahydrofurfuryl alcohol (THFA). The life evaluation test showed that the catalyst still kept high activity and selectivity after being reused five times. The advanced synthesis method co-using N-doped support anchoring and the second metal alloying strategy sheds light on preparing effective catalysts for hydrogenation of biomass-based compounds.
研究领域:
化学工程
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材料科学
·
催化反应
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2024
·
IF 10.7
Zhichao Ma,Chenyi Wang,Tianfang Yang,Gangya Wei,Jinrui Huang,Mengran Liu,Kun Zhang,Zunjie Zhang,Yang Liu,Shuyan Gao
Electrocatalytic nitrate (NO3−) reduction to ammonia (NH3) (NRA) is of great significance for solving the problem of urgent NO3− pollution in the environment and opening up a new route to synthesize NH3. However, NRA is limited by its multi-electron/proton transfer process and the NRA process relies heavily on atomic H* produced by H2O splitting, undergirding the necessity for effective NRA catalysts. Herein, three-dimensional (3D) porous phosphorus (P)-doped Cu–Ni alloy materials are constructed through a one-step electrodeposition synthesis. 3D porous materials modulate hydrophilicity and enrich active sites. The Cu d-band center can be tuned through Ni alloying to modify the adsorption energies of intermediates such as *NO3−, *NO2−, and *NH2. The hydrogenation evolution capacity of P promotes the hydrogenation process in the atomic H* path and effectively accelerates the NRA reaction rate. Density functional theory (DFT) calculations demonstrate that the charge transfer between the negatively charged Pδ− and the positively charged Niδ+ and Cuδ+ assists in generating more atomic H* for coupling with reaction intermediates, showing an enhanced catalytic activity at low overpotential. The optimal sample exhibits an exceptional NRA performance with an ammonia yield rate of 848.1 μmol h−1 cm−2 and a faradaic efficiency of 96.1%. This work provides a strategy for creating effective NRA catalysts through enhancing the atomic H* reduction strategy.
研究领域:
环境科学
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材料科学
·
电催化
✓ 已验证
产品关联
DOI
高影响因子
ENERGY & FUELS
·
2023
·
IF 5.3
Yi Ren,Yujia Bai,Genxiang Wang,Yijian Liu,Chuancheng Mou,Jiayu Chen,Baohuan Wei,Hui Wang,Yuhan Sun
Efficient conversion of CO2 to value-added fuels or chemicals using electricity from renewable sources is an appealing approach to realize carbon neutrality. Under this background, it is crucial to design efficient and low-cost catalysts for CO2 electroreduction. Herein, we fabricated an electrocatalyst with the structure of Cu–Ni alloy nanoparticles grown on nitrogen-doped carbon nanotubes (CuxNi/NCNT, x = 2.4, 1, and 0.36) for electrochemical CO2 reduction reaction (CO2RR) via a hydrothermal method followed by pyrolysis. The optimized CuNi/NCNT demonstrates a favorable CO2RR performance with a CO Faradaic efficiency (FECO) of 94.8% and a current density of 26.6 mA cm–2 at −0.9 V versus the reversible hydrogen electrode (vs RHE) in the H-cell, far superior to those of single metal counterparts. Density functional theory (DFT) calculations unravel that the Cu–Ni alloys possess much lower free energy changes for the formation of the key COOH* intermediate than those of the Cu metal, thereby facilitating CO2 reduction into CO. Additionally, the CO2RR performance of CuNi/NCNT was further evaluated in the gas diffusion electrode (GDE) involved in the flow cell to examine the practical application of the prepared catalyst, which can deliver a current density of 124.6 mA cm–2 with a FECO of 92.8% at −1.1 V vs RHE. This work enriches electrocatalysts for highly efficient CO2 electroreduction to CO.
研究领域:
材料科学
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催化化学
·
能源转换
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2019
·
IF 6.97
Changhui Zhu,Haiyong Wang,Hu Li,Bijuan Cai,Wei Lv,Chiliu Cai,Chenguang Wang,Long Yan,Qiying Liu,Longlong Ma
Alloyed Cu−Ni encapsulated in carbon was prepared by loading Ni and Cu onto biochar (BC) through an initial wetness impregnation method under mild conditions. The bimetallic catalysts were exploited to perform selective hydrodeoxygenation (HDO) of 5-hydroxymethylfurfural (HMF). 2,5-Dimethylfurfural (DMF), a promising liquid fuel/fuel additive, could be obtained from HMF with the highest yield of 93.5% under the optimized conditions. During HMF HDO, two key intermediates, 5-methylfurfural (MFF) and 2,5-dihydroxymethylfuran (DHMF), dominating two distinct conversion pathways were systematically investigated by Arrhenius kinetics analysis. In addition, the turnover frequencies (TOFs) of HDO reaction over Cu−Ni/BC corresponding with Cu amount were thoroughly discussed, finding that the electron transfer from Cu to Ni in the alloy structure was beneficial to the HDO reaction and the conversion pathways can be regulated by reaction temperature variation. Importantly, the synergy of HDO of HMF by alloyed Cu−Ni metal and Lewis acid sites from oxide NiOx were hence clarified by systematic catalyst characterizations. The Cu−Ni/BC catalyst is stable for at least five consecutive runs to obtain the stabilized 81.9% of DMF since the third run.
研究领域:
催化
·
化学工程
·
可再生能源
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2024
·Vol. 171
·期 5
·053507
·
IF 3.1
Wenzheng Wu,Xiaojie Tang,Jing Wang,Chenghan Zhao
With the rapid development of electronics, additive manufacturing of complex three-dimensional microscale metal and alloy structures has emerged as one of the future directions for advanced technologies. In this study, a localized electrochemical deposition technique was developed which enables the fabrication of microscale three-dimensional metal structures in an ambient environment. Notably, we investigated the effects of voltage, initial electrode gap, and electrolyte composition on the deposition of Cu-Ni alloy. Furthermore, we successfully fabricated Cu-Ni equiatomic micro-columns, providing possibilities for the micro/nanoscale fabrication of commercial K-Monel copper. Finally, based on these foundations, we successfully shaped overhanging structures with various angles as well as an "H" structure using a rotating cathode substrate, demonstrating their potential in the fabrication of Cu-Ni alloy micro components.
研究领域:
材料科学
·
电化学
·
微制造
·
增材制造
✓ 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）