Energy Materials
·
2024
·Vol. 4
·期 6
·N
·
IF 11.8
Zuwei Xu,Ze Zhang,Fuchang Gao,Yuhan Zhu,Haibo Zhao
Catalytic combustion is an effective approach to remove air pollutants from various emission sources. For this purpose, supported noble metal catalysts are preferred in commercial applications due to their outstanding catalytic activity for eliminating CO, hydrocarbon compounds and NOx. In this paper, we employ the flame spray pyrolysis method to prepare a series of Pt-based catalysts with four different supports (TiO2, ZrO2, MgO and ZnO) and variable low Pt loadings for catalytic combustion of CO and CH4. The performance of 0.5 Pt/TiO2 is the best in all samples, in which the T90 temperatures are 107 and 500 °C for 90% conversion of CO and CH4, respectively. To examine its thermal stability, a time-on-stream test at 700 °C for 420 min is carried out, resulting in a decrease of about 5% in the final conversion of CH4. The X-ray diffraction results show that TiO2 support is a mixed phase with a major amount of anatase and a small amount of rutile other than a pure phase of ZrO2, MgO and ZnO. Furthermore, X-ray photoelectron spectroscopy analysis and high-angle annular dark-field scanning transmission electron microscopy observation show that when the Pt loading is low, the Pt species exist as highly dispersed single atoms on the surface of the TiO2 support. As the Pt loading gradually increases, the state of the Pt species transitions from single atoms to Pt clusters, resulting in a decrease in dispersion. Ultimately, the Pt can successfully accumulate on the surface of the TiO2 nanoparticles, providing abundant active sites for efficient catalytic combustion reactions.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
CATALYSIS LETTERS
·
2020
·Vol. 150
·期 7
·2045-2055
·
IF 2.482
Li Chaoqun,Yang Yang,Ren Wei,Wang Jian,Zhu Tingyu,Xu Wenqing
Abstract CO is toxic and detrimental to human beings and the atmosphere. The presence of CO has become one of the important indicators for evaluating ambient air quality. Iron and steel sintering generate large amounts of flue gas emissions containing approximately 1% CO, which has become an important factor restricting the improvement of air quality in steel cities. The catalytic oxidation method is the simplest and most effective method for CO emission control. In this work, a series of Cu x Ce y /TiO 2 catalysts with different Ce doping levels were prepared by a one-step impregnation method and subsequently tested for catalytic CO oxidation. The Cu 0.5 Ce 0.5 /TiO 2 sample has the best catalytic activity under the conditions of 1% CO and 10% H 2 O. The catalysts were next characterized by XRD, BET, TEM, H 2 -TPR, XPS and in-situ DRIFTS methods. The characterization results show that Ce doping promotes the dispersion of copper species on the catalyst surface and improve the redox performance of the catalyst. The results of in-situ experiments showed that both Cu/TiO 2 and Cu 0.5 Ce 0.5 /TiO 2 catalysts followed Mars and van Krevelen mechanism, and Ce doping enhanced the adsorption and activation of oxygen, thus improving the low-temperature reaction activity of the catalysts. Graphic Abstract
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2017
·
IF 9.446
Wenhui Li,Xiaowa Nie,Xiao Jiang,Anfeng Zhang,Fanshu Ding,Min Liu,Zhongmin Liu,Xinwen Guo,Chunshan Song
Screening of various supports reveals that Co catalysts supported on ZrO 2 and Al 2 O 3 show good initial activity for CO 2 methanation. Co/ZrO 2 and Co/Al 2 O 3 catalysts prepared by impregnation with different metal loadings were further examined comparatively. The 10Co/ZrO 2 catalyst showed high activity with CO 2 conversion of 92.5% and CH 4 selectivity of 99.9% without deactivation after 300 h time on stream (TOS). However, the 10Co/Al 2 O 3 catalyst gave a lower CO 2 conversion of 77.8% which decreased to 38.6% after 300 h TOS. The catalysts were characterized by STEM/EDS (scanning transmission electron microscopy/energy-dispersive X-ray spectroscopy), in situ XRD(X-ray diffractometer), H 2 -TPR(temperature programmed reduction), XPS (X-ray photoelectron spectroscopy), chemisorption of H 2 , CO, CH 4 , CO 2 and NH 3 -TPD (temperature programmed desorption). Re-dispersion of Co species on the ZrO 2 support during reduction by H 2 was observed by STEM/EDS. New Co-Zr phase formed on the Co-ZrO 2 interface was directly observed by TEM for the first time; the Co/ZrO 2 catalyst exhibited high stability with high activity for CO 2 conversion. In situ XRD, H 2 -TPR and XPS results indicate the promoting effect of ZrO 2 on the reduction of Co 3 O 4 to Co metal along with the negative effect of Al 2 O 3 . The oxygen vacancies on the ZrO 2 detected by XPS may help to activate CO 2 and H 2 O and resist deactivation. Co/Al 2 O 3 catalyst deactivates rapidly due to coke deposition and spinel formation.
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
Journal of the Taiwan Institute of Chemical Engineers
·
2016
·
IF 2.848
Huan Liu,Yi Lin,Zhen Ma
Au/M-P-O (M = Mg, Al, Ca, Fe, Co, Zn, La) catalysts were prepared by loading ca. 1 wt.% gold onto commercial metal phosphate supports by deposition-precipitation with urea (DPU), and tested in CO oxidation. Au/La-P-O showed the highest activity, achieving complete CO conversion at 70 °C. Au/Ca-P-O was the second most active, achieving complete CO conversion at 155 °C. The remaining catalysts were not active below 200 °C. In view of the results, we additionally prepared Au/LaPO 4 nanowires by loading ca. 1 wt.% gold onto LaPO 4 nanowires via DPU. The Au/LaPO 4 nanowires catalyst was even more active, achieving complete CO conversion at 15 °C. The catalysts were characterized by N 2 adsorption-desorption, inductively coupled plasma optical emission spectroscopy (ICP-OES), X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and temperature-programmed desorption of O 2 or CO 2 (O 2 -TPD, CO 2 -TPD). Reasons for the higher activity of Au/LaPO 4 nanowires were discussed.
研究领域:
材料科学
·
催化化学
✓ 已验证
DOI
高影响因子
Molecular Catalysis
·
2024
·
IF 3.9
Xingling Zhao,Xue Zhou,Wanyan Xing,Zhimin Yuan,Kaili Wang,Qihang Zhang,Yulong Shan,Jiani Liu,Lin Ju,Zaiyong Jiang,Hong He
CO is a ubiquitous air pollutant, frequently encountered in the fields of automotive exhaust purification, especial in the cold-start-emission stage. Pt based catalysts are widely used to purify CO into CO 2 owing to their exceptional performance. But they can be few excited to exhibit reasonable catalytic activity due to the low temperature at the cold-start-emission stage. In exhaust gas purification catalysts used by fossil fuel-based vehicles, Al 2 O 3 is used frequently. But there are rarely reports of Pt loaded Al 2 O 3 catalysts achieving feasible activity of CO oxidation at room temperature. Herein, we prepared Cu x Pt y alloy/Al 2 O 3 catalysts (with high penta-coordinated Al 3+ (Al V )), Al V centers as binding sites for Cu 3 Pt 1 alloys on Al 2 O 3 enable the high dispersion and stability of Cu 3 Pt 1 alloy. The adsorption capacity of O 2 and CO molecules on Cu 3 Pt 1 surface are stronger than the case on Pt surface, which may make O 2 and CO molecules more easily activated, making the CO oxidation reaction easier. In addition, the desorption of CO 2 from Cu x Pt y surface is easier compared to that on Pt surface, increasing the frequency of use of active sites there. Therefore, this Cu 3 Pt 1 /Al 2 O 3 catalyst exhibits 100 % conversion of CO with a GHSV of 6×10 3 mL·g −1 cat ·h −1 at room temperature. This work provides a feasible guideline for the design and synthesis of Pt loaded Al 2 O 3 catalysts toward room temperature CO oxidation.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
SYNTHETIC METALS
·
2025
·
IF 4.6
Yu Lin,Gen Li,Juan Teng,Haibo Wang,Ximei Liu
As a crucial component of flexible electronic devices, poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS)-based hydrogels for strain sensors have garnered extensive attention for their potential in the field of wearable sensors due to their inherent conductivity and flexibility. However, challenges such as poor mechanical strength, limited sensitivity, and poor durability have hindered the widespread application of PEDOT:PSS hydrogels in high-performance strain sensors. In this study, we develop a novel PEDOT:PSS-P(HEMA-co-AA) hydrogel that addresses common limitations in hydrogel applications, demonstrating remarkable stretchability, low hysteresis, and reliable conductivity. The hydrogel is synthesized using a semi-interpenetrating polymer network (SIPN) strategy, combining the linear conducting polymer PEDOT:PSS with a chemically cross-linked network based on 2-hydroxyethyl methacrylate (HEMA) and acrylic acid (AA). This hybrid structure notably contributes to the hydrogel's mechanical properties, achieving a stretchability of 195 %, while maintaining a rapid response time of 0.20 seconds and exceptional cyclic stability over 1000 cycles under 100 % strain. Moreover, the hydrogel demonstrates promising strain-sensing capabilities, positioning it as a strong candidate for future applications in wearable electronics and flexible sensors. The adoption of the SIPN strategy, along with the synergistic combination of PEDOT:PSS and P(HEMA-co-AA), paves a new pathway for enhancing the mechanical performance and sensing properties of hydrogels in strain-sensing technologies.
研究领域:
材料科学
·
柔性电子
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
REACTIVE & FUNCTIONAL POLYMERS
·
2016
·
IF 2.725
Luanluan Zhang,Hejun Gao,Yunwen Liao
A series of functional cross-linked polymer (Poly(AMPS- co -DVB)) were synthesized by 2-acrylamido-2-methylpropane sulfonic acid (AMPS) and divinylbenzene (DVB). The physicochemical properties of the Poly(AMPS- co -DVB) were characterized by FT-IR, TGA , SEM, XRD , Zeta potential and UV–Vis. Those results showed that the Poly(AMPS- co -DVB) could provide mounts of adsorption sites from its special structure. The effects of the initial pH, dosage, contact time, and temperature on the adsorption of Rhodamine B (RhB) onto the Poly(AMPS- co -DVB) were investigated. It was found that the initial pH was an important factor for the molecules form of RhB and the surface formation of Poly(AMPS- co -DVB). With increasing of molar ratio of AMPS/DVB, the adsorption efficiency increased gradually. In the adsorption process , both physical and chemical mechanism is presence to adsorb RhB. The maximum adsorption capacity could get 407.9 mg/g within 2 h at room temperature .
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
RENEWABLE ENERGY
·
2025
·
IF 9.1
Hongming Liu,Junhao Cui,Zhiyang Zhao,Yongqi Ren,Bailong Chen,Longzhi Li
The traditional utilization of lignin mainly relies on direct combustion, which leads to low energy efficiency and environmental pollution, becoming a key bottleneck restricting the efficient utilization of all components of lignocellulose. This paper introduced a new strategy of microwave-assisted lignin hydrogenolysis over bifunctional catalyst Fe-Co/AC to achieve high-value conversion of lignin. This article firstly investigated the hydrogenolysis characteristics and product distribution patterns in the presence of Fe-Co/AC through catalyst characterization and adsorption calculation, as well as hydrogenolysis experiments. The results showed that the formation of Fe-Co alloy in the catalyst resulted in highly catalytic activity and selectivity for the hydrogenolysis process. Next, the intrinsic effects of solvent hydrogen donors and microwaves on lignin hydrogenolysis were discussed, through comparative experiments of hydrogenolysis in absence of catalyst and microwave-assisted pyrolysis. Lastly, attention was paid to calculate the adsorption characteristics and bond length changes of different substrates under metal components in order to reveal the mechanism of Fe-Co for synergistic catalyzing lignin hydrogenolysis, and to propose a potential pathway for lignin directed conversion into phenol. The findings provide a new approach for efficient bond breaking and intermediates hydrogenation of solid wastes such as lignin and plastics to obtain high value-added products.
研究领域:
化学工程
·
环境科学
✓ 已验证
DOI
高影响因子
Journal of the Taiwan Institute of Chemical Engineers
·
2016
·
IF 2.848
Huan Liu,Zhen Ma
LaPO 4 has been used as a support to make supported catalysts in some investigations, but the effect of different LaPO 4 supports on the catalytic performance of supported catalysts has been rarely reported. In this work, conventional hexagonal LaPO 4 (LaPO 4 H) was prepared by precipitation, and hexagonal LaPO 4 nanowires (LaPO 4 HNW) was prepared by hydrothermal synthesis at 150 °C. Monoclinic LaPO 4 nanowires (LaPO 4 -MNW-220 and LaPO 4 -MNW-900) were prepared by hydrothermal synthesis at 220 °C or calcining LaPO 4 HNW at 900 °C. These samples were used to support Rh 2 O 3 via impregnation using Rh(NO 3 ) 3 as a precursor. The activities of these supported catalysts in N 2 O decomposition and CO oxidation follow the same sequence of Rh 2 O 3 / LaPO 4 HNW > Rh 2 O 3 / LaPO 4 H > Rh 2 O 3 / LaPO 4 -MNW-220 > Rh 2 O 3 / LaPO 4 -MNW-900, i.e. , two hexagonal LaPO 4 supports are better than two monoclinic LaPO 4 supports in making active catalysts, and hexagonal LaPO 4 nanowires are better than hexagonal LaPO 4 composed of nanoparticles and short nanorods. The most active catalyst has highly dispersed Rh 2 O 3 species interacting strongly with the support, more oxygen-adsorption capacity, and more basic sites.
研究领域:
催化化学
·
材料科学
✓ 已验证
DOI
高影响因子
MOLECULES
·
2024
·Vol. 29
·期 10
·2349
·
IF 4.2
Ziwei Deng,Wei Liu,Junyuan Zhang,Shuli Bai,Changyu Liu,Mengchen Zhang,Chao Peng,Xiaolong Xu,Jianbo Jia
A Fe-Co dual-metal co-doped N containing the carbon composite (FeCo-HNC) was prepared by adjusting the ratio of iron to cobalt as well as the pyrolysis temperature with the assistance of functionalized silica template. Fe1Co-HNC, which was formed with 1D carbon nanotubes and 2D carbon nanosheets including a rich mesoporous structure, exhibited outstanding oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) catalytic activities. The ORR half-wave potential is 0.86 V (vs. reversible hydrogen electrode, RHE), and the OER overpotential is 0.76 V at 10 mA cm−2with the Fe1Co-HNC catalyst. It also displayed superior performance in zinc–air batteries. This method provides a promising strategy for the fabrication of efficient transition metal-based carbon catalysts.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MICROCHIMICA ACTA
·
2022
·Vol. 189
·期 9
·1-11
·
IF 6.408
Sun Wenying,Wang Nan,Zhou Xiaobin,Sheng Yuxuan,Su Xingguang
A Co, N co-doped porous carbon-based nanozyme (Co–N-C nanozyme) has been fabricated. Taking advantages of the excellent oxidase catalytic activity and significant stability of Co–N-C nanozyme, we propose a fluorescence and colorimetric system based on Co–N-C nanozyme and red-emitting carbon quantum dots (RCDs) for butyrylcholinesterase (BChE) sensing. As the chromogenic substrate 3,3′,5,5′-tetramethylbenzidine (TMB) was catalyzed and oxidized by Co–N-C nanozyme, the generated oxTMB had a new absorption peak at 652 nm, which resulted in the significant quenching of the fluorescence of the carbon quantum dots at 610 nm. Under the catalysis of BChE, thiocholine was generated from the hydrolysis of S-butyrylthiocholine iodide (BTCh), and the as-generated thiocholine effectively inhibited the oxidation of TMB catalyzed by Co–N-C nanozyme, leading to a decrease of the absorption of oxTMB at 652 nm and effective fluorescence recovery of RCDs. By measuring the absorbance of produced oxTMB at 652 nm and the fluorescence of RCDs at 610 nm, the fluorescence and colorimetric system both exhibited an outstanding linear response to the activity of BChE in the range 0.5 to 40 U L −1 , with a detection limit of 0.16 U L −1 and 0.21 U L −1 , respectively. Furthermore, this established dual-channel biosensing strategy has been successfully applied to the determination of BChE in human serum samples. The present work has effectively expanded the development and application of nanozyme in biosensing. Graphical abstract
研究领域:
生物化学
·
纳米生物学
·
分析化学
✓ 已验证
DOI
PubMed
高影响因子
Materials Today Communications
·
2021
·
IF 3.383
Xiao-Hui Yang,Kai-Fei Wang,Kuo-Chih Chou,Guo-Hua Zhang
Fine grained WC-Co-Ni cemented carbides with a low binder content have been successful manufactured via the powder metallurgy method. The WC-Co-Ni composite powder with homogeneous distributions of Co and Ni was synthesized by chemical co-precipitation with the raw materials of WC powder, oxalic acid and chlorides of Co and Ni. In this study, the effects of cobalt and nickel contents on the properties of cemented carbides were investigated systematically. The experimental results demonstrated that the alloy prepared by vacuum sintering had uniform grain size distribution and no abnormal growth of WC grains. When the cobalt content was 4 wt% and 5 wt%, the obtained composites almost completely consolidated with excellent hardness and fracture toughness. Among them, for the sample WC-4 wt%Co, the relative density could reach 99.37%, and the Vickers hardness and fracture toughness were 2010 HV 30 and 8.55 MPa·m 1/2 , respectively. When Ni was added to replace part of Co, the relative density of WC-Co-Ni decreased and the fracture toughness was improved without basically sacrificing the hardness. For the sample WC-2 wt%Co-2 wt%Ni, the hardness decreased to 1921 HV 30 , while the fracture toughness increased to 8.97 MPa·m 1/2 .
研究领域:
材料科学
·
粉末冶金
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）