Catalysis Science & Technology
·
2015
·Vol. 5
·期 4
·2260-2269
·
IF 5.426
Qiulin Zhang,Xin Liu,Ping Ning,Zhongxian Song,Hao Li,Junjie Gu
Mesoporous Ce–Ti–MoOx catalysts have been prepared by stabilization with an in situ formed carbon template and used for selective catalytic reduction of NOx with NH3 (NH3-SCR). The Ce–Ti–MoOx catalysts were characterized by N2 adsorption–desorption, XRD, HR-TEM, H2-TPR and XPS analysis. It was found that the stabilization with a carbon template obviously improved the NOx conversion of the Ce–Ti–MoOx catalyst and the pore distribution. The Ce–Ti–MoOx catalyst stabilized with a carbon template at 850 °C in N2 exhibited the best NH3-SCR activity and showed a uniform mesopore distribution, and more than 90% NOx conversions were obtained at 175–425 °C with a GHSV of 60 000 h−1. The high stabilization temperature with a carbon template in N2 not only led to an increase in specific surface area, pore volume and low-temperature SCR activity, but also contributed to the enhanced redox properties, highly dispersed titanium or molybdenum species and narrow mesopore distribution. The treatment of Ce–Ti–MoOx with a high calcination temperature for removal of the carbon template led to a drastic decrease in surface area, an abrupt decrease in surface oxygen and cerium, production of rutile TiO2, and a correspondingly low SCR activity.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
Advanced Composites and Hybrid Materials
·
2021
·Vol. 4
·期 3
·815-818
·
IF 5.693
Zeng Yanxian,Li Qijie,Niu Xiaochun,Wang Suying,Smith Andrew T.,Zheng Mingtao,Sun Luyi,Wang Weixing
Photoluminescent mesoporous silica with a surface area of 840 m 2 /g, pore diameter of 4.8 nm, and pore volume of 0.69 cm 3 /g was synthesized through the calcination of Pluronic 123 (P123) and cetyltrimethylammonium bromide (CTAB) co-templated mesoporous silica at 400 °C for 2 h. The photoluminescence is from the trapped carbon derived from the co-templates. Graphical abstract
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2024
·Vol. 16
·期 9
·4600-4608
·
IF 5.8
Chunxue Zheng,Xinyang Li,Jie Yu,Zhulin Huang,Ming Li,Xiaoye Hu,Yue Li
Silicon carbide (SiC) aerogels, which possess unique porous structure and high ablation resistance, show great potential as thermal insulation materials, but their wide application is limited by expensive and cumbersome synthetic procedures. Therefore, it is pivotal to develop a facile, versatile, and cost-effective method for producing SiC aerogels. Herein, we have successfully prepared ultra-light SiC nanowire aerogels (SNWAs) boasting remarkably low thermal conductivity, using biomass-derived carbon templates (BCTs) through a direct carbothermal reduction method. The BCTs obtained by simply carbonizing freeze-dried eggplants can serve not only as the carbon sources but also as the templates for the in situ growth of SiC nanowires. The resultant three-dimensional (3D) SNWAs possess various porous structures, incorporating the original micro-sized pores inherited from the eggplant and nano-sized pores constructed from interconnected SiC nanowires. These multi-scale pore structures bestow SNWAs with lower gas-phase heat conduction characteristics. Besides, the numerous stacking faults and heterojunctions present in the SiC nanowires play a key role in obstructing the solid-phase heat transfer and reinforcing the SiC skeleton. As a result, the SNWAs show an exceptionally low thermal conductivity, measuring 0.0149 W m−1 K−1 at room temperature, and maintain this low value (0.0256 W m−1 K−1) even at 500 °C. Remarkably, even after being exposed to air at 1200 °C for 2 h, the SNWAs maintain a low thermal conductivity of 0.0226 W m−1 K−1. Such low-cost and effective preparation of biomass-derived SiC aerogels is anticipated to pave a new avenue for the development of advanced thermal insulators.
研究领域:
材料科学
·
能源工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENERGY & FUELS
·
2016
·
IF 2.835
Pengfei Zhao,Ji Sun,Yimin Li,Ke Wang,Zeguang Yin,Zhongyun Zhou,Zhen Su
A facile carbon template method was employed to modify the microstructure of calcined organometallic calcium compounds (i.e., calcium acetate, calcium citrate, and calcium gluconate) for high-temperature CO2 capture. The effects of the decomposition atmosphere, carbon source, and pyrolysis temperature on the physical and chemical properties as well as the cyclic CO2 capture performance were determined using various morphological characterization techniques and detailed thermogravimetric analysis. During pyrolysis in an inert atmosphere, in situ carbon formed from organometallic calcium compounds, which served as a template for controlling the sintering of CaCO3, and the subsequent carbon burnoff in air promoted the fabrication of porous CaO. Among the three organometallic calcium compounds, the pyrolysis process of calcium gluconate exhibited the earliest carbonization and the template with the highest organic carbon content and the slowest decomposition of CaCO3. Therefore, the most favorable structure (i.e., the smallest crystal size, largest specific surface area, and largest pore volume of CaO) was obtained from calcium gluconate, which was responsible for the fastest adsorption rate, highest capacity, and best stability. Moreover, this superior performance was maintained when the pyrolysis temperature was approximately 600–800 °C.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2022
·
IF 8.035
Ji Zhao,Jing-Hui Lv,Xian-Yong Wei,Qian-Qian Kong,Jia-Hao Li,Yang-Yang Zhang,Zhuang Li,Li Li,Zi-Chun Fan,Zhi-Min Zong
Ni/CeO 2 -La 2 O 3 with strong acidity was prepared by in - situ carbon templating (ISCT) and subsequent reduction with H 2 . The phase composition, specific surface area, morphology, acidity, and elemental valence composition of the catalyst were characterized. The catalytic methylation (CM I ) of phenol over the catalyst in different ratios of methanol to n -hexane was investigated under N 2 atmosphere. Over the catalyst, phenol was completely converted into 2,6-xylenol at 260 °C for 3 h via the CM I of phenol to o -cresol and subsequent CM I of o -cresol.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2024
·
IF 4.8
Yuqing Ouyang,Ningning Du,Xiaoyun Xiong,Qingxun Hu,Hongman Sun,Tingting Li,Jie Zhong,Youhe Wang,Zifeng Yan
The combination of titanium silicalite-1 (TS-1) zeolite and H 2 O 2 oxidant provides an excellent alternative to many highly toxic and polluting olefin oxidation processes due to the by-product being water-only and without deep oxidation. However, the diffusion of bulky reactants and products suffers from the inherent micropores of conventional TS-1 zeolites. Herein, we designed a reticulated ordered macroporous carbon material with uniform and coherent mesopores, and successfully synthesized ordered hierarchical TS-1 zeolites containing intracrystalline macroporous-mesoporous-microporous by dry gel method. The fully interconnected intracrystalline macroporous-mesoporous-microporous hierarchical TS-1 improves the accessibility of the active site and the diffusion efficiency of bulky compounds. It showed excellent catalytic performance during the epoxidation reaction of chloropropene, and its epichlorohydrin yield and H 2 O 2 effective utilization were 70.11% and 77.05%, which were 2.2 and 1.9 times of the catalytic performance of commercial TS-1 zeolites, respectively, and significantly better than the ultrafine TS-1 synthesized by conventional methods. The high catalytic performance was maintained after three cycles of use. This offers a good opportunity for the design and synthesis of efficient zeolite catalysts in the future.
研究领域:
材料科学
·
化学工程
·
催化
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Zheqin Chen,Yongmin Xie,Zhibin Lu,Xiaocong Zhong,Zhifeng Xu
This research addresses the issue of particle agglomeration and a low catalytic activity in the traditional sol–gel preparation of LaNi 0.5 Co 0.5 O 3 (LNCO). A new synthetic strategy is proposed, leveraging the combination of polyvinylpyrrolidone (PVP) serving as a complexing agent and graphene nanosheet (GN) functioning as a template, successfully producing a high-activity LNCO cathode material (GN-LNCO) with a layered structure. Various characterizations confirmed that incorporating PVP and GN effectively suppressed particle agglomeration at high temperatures. The optimized GN-LNCO exhibited excellent physicochemical properties, including a specific surface area of 45.21 m 2 g −1 , a more regular mesoporous structure, a higher electronic conductivity, and a greater oxygen vacancy concentration. Electrochemical performance tests showed that the GN-LNCO cathode demonstrated an outstanding performance in solid oxide fuel cells at 800 °C, with a peak power density of 350.91 mW cm −2 . This represented an improvement of 28.65% over the conventional LNCO. Additionally, a 72 h long-term stability test of a GN-LNCO single cell revealed a voltage decay rate of only 1.60%, indicating its excellent stability. Overall, this study provides a novel material design strategy for developing high-performance cathodes, which has significant implications for advancing solid oxide fuel cell technologies.
研究领域:
材料科学
·
电化学
·
能源技术
·
纳米技术
·
无机化学
✓ 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）