Journal of Materials Chemistry A
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2020
·Vol. 8
·期 14
·6524-6531
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IF 11.301
Jiadong Li,Feng Wei,Changchang Dong,Wei Mu,Xiaojun Han
Indium oxide (In2O3)-based photocatalysts have great potential in photocatalytic CO2 reduction. Nevertheless, their photocatalytic activity is inhibited by rapid electron–hole recombination. Hence, a novel Z-scheme ternary hierarchical ZnFe2O4/RGO/In2O3 photocatalyst is fabricated for photocatalytic conversion of CO2 to CO and CH4. The CO production rate reaches up to 35.4 μmol g−1 under 4 h of illumination using a 20ZFO/10RGO/IO catalyst, which is 3.9 times and 9.8 times higher than those using bare In2O3 and bare ZnFe2O4, respectively. The CH4 production rate is 7.8 μmol g−1, which is 4.3 fold and 2.4 fold higher, respectively, compared to those from bare In2O3 and bare ZnFe2O4. The enhancement of photocatalytic CO2 reduction was ascribed to a Z-scheme mechanism of the hierarchical catalysts by introducing RGO in-between In2O3 and ZnFe2O4 to promote charge separation and realize efficient utilization of the high-energy electrons and holes. The oxygen-defect of ZnFe2O4 also facilitates the adsorption and activation of CO2. This work provides new insights to design ternary In2O3-based hierarchical photocatalysts with a rational Z-scheme photocatalytic mechanism to improve the CO2 conversion efficiency.
研究领域:
材料科学
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环境科学
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DOI
高影响因子
Journal of the Taiwan Institute of Chemical Engineers
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2019
·
IF 3.834
Shenhao Yuan,Xushuai Lv,Yiwei Zhang,Yangjin Wu,Chunfeng Mao,Yuming Zhou,Wenxia Chen,Yanyun Wang
A core-shell structure Au-based catalysts mSiO 2 /Au/Co 3 O 4 HS were successfully derived from in-situ growth ZIF-67 hollow spheres, which were synthesized by a one-step soft template method. The samples were characterized by SEM, TEM, EDX, XPS, XRD and BET to confirm its successful preparation and structural features. The catalytic performance of the catalysts were evaluated by liquid phase oxidation of benzyl alcohol to benzaldehyde with O 2 as the oxidant under alkaline conditions. The experimental results illustrated that reaction conditions, including effect of catalyst amount, oxygen flow rate, reaction temperature and reaction time, were optimized to be 40 mg, 50 ml/min, 140 °C and 5 h, respectively. Meanwhile, 55% conversion of benzyl alcohol and 84% selectivitiy to benzaldehyde together with the excellent reusability and stability were achieved under optimal reaction conditions, which was attributed to the core-shell structure leading to the encapsulation of Au NPs and provision of multiple active reaction interface. Based on the intermediates formed from the de-protonation of substrate, a plausible oxidation reaction mechanism with mSiO 2 /Au/Co 3 O 4 HS catalysts was tentatively proposed to study the relationship between structure and catalytic performance.
研究领域:
材料科学
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催化化学
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DOI
高影响因子
Molecular Catalysis
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2024
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IF 3.9
Wen-Xia Zhang,Xi Zhao,Lin-Ya Xu,Shuang Xia,Yu-Fen Zhou,Chong-Lai Chen,Hai-Hua He,Meng-Fei Luo,Jian Chen
The surface Pt species and adsorbed oxygen on the Pt/ZrO 2 catalyst were successfully modulated by altering the preparation methods, resulting in distinct catalytic behaviors for CO, n-heptane, and toluene oxidation. The Pt/ZrO 2 catalyst was initially prepared via wetness impregnation and subsequently reduced in an H 2 atmosphere to obtain the Pt/ZrO 2 -R catalyst. In contrast, the Pt/ZrO 2 -E catalyst was synthesized using ethanol solvent (also serving as a reducing agent) instead of water during wetness impregnation. Moreover, the pre-prepared Pt nanoparticles were loaded onto the ZrO 2 surface using polyvinylpyrrolidine (as a protective and structure directing agent) dissolved in ethanol solvent to fabricate the Pt/ZrO 2 -EP catalyst. Among these catalysts, the Pt/ZrO 2 -R exhibits superior catalytic activity towards CO oxidation due to its abundant metallic Pt species. It is found that activity of Pt/ZrO 2 catalyst for n-heptane oxidation is positively correlated with its surface adsorbed oxygen concentration, thus the highest activity is achieved over the Pt/ZrO 2 -EP catalyst possessing a higher concentration of surface adsorbed oxygen species. Unlike CO and n-heptane oxidation, toluene oxidation activity is affected by multiple factors, it is primarily promoted by synergistic catalysis between metallic Pt species (Pt 0 ) and surface adsorbed oxygen species over the Pt/ZrO 2 -EP catalyst. Our preliminary findings underscore that precise modulation of sensitive active sites on surfaces plays a critical role in specific catalytic reactions.
研究领域:
催化化学
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材料科学
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环境科学
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DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
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2018
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IF 3.956
Tian-qi Lei,Yan-hu Cheng,Chang-xi Miao,Wei-ming Hua,Ying-hong Yue,Zi Gao
Dehydrogenation of ethane to ethylene in the presence or absence of CO 2 over silica-doped TiO 2 supported Ga 2 O 3 catalysts was investigated. The silica doping of TiO 2 support greatly improved the dehydrogenation activity in the absence of CO 2 , which can be ascribed to the increased acid sites. The initial activity in the presence of CO 2 decreased after the silica doping, due to the reduction in reverse water-gas shift ability. However, the selectivity as well as the stability increased, resulting in higher steady ethylene yield. A dynamic process consisting of alternative oxidative dehydrogenation/regeneration cycles by gasifying the carbon deposit with air for 10 min after each cycle of 6 h reaction was also performed and relatively stable ethane conversion ~30% and ethylene yield ~25% can be achieved. The different catalytic behaviors are probably associated with the different state of gallium species, caused by the different interaction between the Ga 2 O 3 and support.
研究领域:
化学工程
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催化科学
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DOI
高影响因子
Catalysts
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2022
·Vol. 12
·期 5
·493
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IF 4.501
Gengzhe Song,Qi Wang,Liang Yang,Duohua Liao,Shuang Li
A series of the layered double oxides supported molybdenum oxide catalysts were synthesized and evaluated in the oxidative dehydrogenation of ethane with CO2(CO2-ODHE). The 22.3 wt% Mo/LDO catalyst delivered a 92.3%selectivity to ethylene and a 7.9% ethane conversion at relatively low temperatures. The molybdenum oxide catalysts were fully characterized by XRD, BET, SEM, TEM, UV–vis, Raman TG, and XPS. Isolated [MoO4]2−dominated on the surface of the fresh 12.5 wt% Mo/LDO catalyst. With the increase of the Mo content, the Mo species transformed from [MoO4]2−to [Mo7O24]6−and [Mo8O26]4−on the 22.3 wt% and 30.1 wt% Mo/LDO catalysts, respectively. The redox mechanism was proposed and three Mo species including [MoO4]2−, [Mo7O24]6−, and [Mo8O26]4−showed quite different functions in the CO2-ODHE reaction: [MoO4]2−, with tetrahedral structure, preferred the non-selective pathway; [Mo7O24]6−, with an octahedral construction, promoted the selective pathway; and the existence of [Mo8O26]4−reduced the ability to activate ethane. This work provides detailed insights to further understand the relationship between structure–activity and the role of surface Mo species as well as their aggregation state in CO2-ODHE.Keywords:ethane;oxidative dehydrogenation;molybdenum oxide;CO2;Mo/LDO catalyst
研究领域:
化学工程
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催化化学
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DOI
高影响因子
Science Bulletin
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2023
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IF 18.9
Zhaolei Wang,Wenhai Xu,Guoying Tan,Xinxuan Duan,Bichen Yuan,Marshet Getaye Sendeku,Hai Liu,Tianshui Li,Fengmei Wang,Yun Kuang,Xiaoming Sun
Electrocatalytic two-electron water oxidation affords a promising approach for distributed production of H 2 O 2 using electricity. However, it suffers from the trade-off between the selectivity and high production rate of H 2 O 2 due to the lack of suitable electrocatalysts . In this study, single atoms of Ru were controllably introduced into titanium dioxide to produce H 2 O 2 through an electrocatalytic two-electron water oxidation reaction. The adsorption energy values of OH intermediates could be tuned by introducing Ru single atoms , offering superior H 2 O 2 production under high current density . Notably, a Faradaic efficiency of 62.8% with an H 2 O 2 production rate of 24.2 μmol min −1 cm −2 (>400 ppm within 10 min) was achieved at a current density of 120 mA cm −2 . Consequently, herein, the possibility of high-yield H 2 O 2 production under high current density was demonstrated and the importance of regulating intermediate adsorption during electrocatalysis was evidenced.
研究领域:
材料科学
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电化学
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产品关联
DOI
PubMed
高影响因子
Reaction Kinetics Mechanisms and Catalysis
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2019
·Vol. 128
·期 1
·109-120
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IF 1.428
Wu Jiequn,Hua Weiming,Yue Yinghong,Gao Zi
Graphitic carbon nitride (g-C 3 N 4 ) modified Co 3 O 4 was prepared by impregnation and pyrolysis. The obtained g-C 3 N 4 /Co 3 O 4 was thoroughly characterized by XRD, SEM, TEM, FTIR, TG and N 2 adsorption. Its catalytic performance was investigated in the aerobic oxidation of benzyl alcohol in liquid phase. High activity as well as excellent selectivity to benzaldehyde can be obtained at mild condition (at atmospheric pressure and temperature of 80 °C). H 2 -TPR and XPS results show that the excellent activity over modified Co 3 O 4 comes from the cooperative action of g-C 3 N 4 and Co 3 O 4 components. g-C 3 N 4 /Co 3 O 4 can also be used as an efficient catalyst for the aerobic oxidation of various aromatic alcohols. However, it is not active for the aerobic oxidation of aliphatic alcohols.
研究领域:
催化化学
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材料化学
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有机化学
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绿色化学
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能源化学
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DOI
高影响因子
MATERIALS LETTERS
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2025
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IF 2.7
Xiaojiao Yu,Yi Wang,Long Li,Jin Wang,Dun Zhang
To enhance the bactericidal efficacy of TiO 2 /Cu 2 O composite coatings and mitigate the issue of ongoing oxidation, we introduced different sizes of spherical silica as supporting materials, combined with TiO 2 /Cu 2 O, to develop a novel antibacterial, antioxidant photocatalytic system. The synthesized ST and STC samples underwent comprehensive characterization using transmission electron microscopy. Subsequent analyses employing X-ray diffraction and UV–Vis diffuse reflectance systematically validated the preserved structural integrity and enhanced photochemical stability of the developed materials. The introduction of silica spheres not only significantly increased the specific surface areas of TiO 2 and Cu 2 O, thereby enhancing their interfacial contact, but also promoted efficient charge separation of photogenerated electrons and holes. Furthermore, this approach reduced the required amount of TiO 2 and Cu 2 O, leading to cost savings. These advantages make the developed coating highly suitable for industrial-scale sterilization applications.
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高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2024
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IF 3.8
Guangyu Zhang,Ningkun Xu,Bing Sun,Feng Sun,Xinmei Liu,Wei Xu,Zhe Yang
The direct synthesis of propylene carbonate (PC) through a tandem epoxidation-cycloaddition reaction from propylene and CO2 is considered a highly promising industrial process due to its streamlined procedure, atomic efficiency, cost-effectiveness, and inherent safety. In this work, we investigated the thermal stability of oxidants critical for the tandem epoxidation-cycloaddition reaction, aiming to determine the optimal oxidant between hydrogen peroxide (H2O2) and cumene hydroperoxide (CHP). This evaluation is particularly significant given the tendency of oxidants to decompose at a higher temperatures required for the cycloaddition reaction. Our findings indicate that CHP is a superior oxidant for facilitating the tandem epoxidation-cycloaddition coupling at high reaction temperatures, due to its higher decomposition temperature (122 °C) compared to H2O2 (40 °C). Furthermore, we present for the first time a one-pot synthesis of PC through a tandem epoxidation-cycloaddition reaction using CHP as the oxidant for the epoxidation step, achieving PC yield of 79.8%. Additionally, a plausible reaction mechanism for this tandem epoxidation-cycloaddition reaction of propylene and CO2 is proposed, based on experimental observations and supported by density functional theory (DFT) calculations. Specifically, DFT calculations reveal that the synergistic effect between hydroxyl groups and Br– promotes the ring-opening of propylene oxide (PO).
研究领域:
化学工程
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环境科学
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催化化学
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DOI
高影响因子
ACS Earth and Space Chemistry
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2023
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IF 3.4
Hao Tian,Xue-Bin Zhang,Yin-Ping Li,Qing He,Na-Na Tian,Song-Hai Wu,Xu Han
Although inorganic Fe(IV)═O oxo and Fe(III)-OOH peroxo have attracted more attention in aqueous environments, direct evidence for the characterization and identification of those oxidizing species is still lacking. In this study, the doped Cu/Co increases the reactivity of ferrihydrite/hematite in oxidizing As(III) by S(IV)-O2 under alkaline and dark conditions. Quenching experiments exclude the contributions of ·OH, O2•–, SO3•–, SO4•–, SO5•–, HSO5–, and H2O2 and confirm that peroxo and oxo are primary oxidizing species in As(III) oxidation. Electrochemical analyses indicate that Fe(IV)═O oxo and Fe(III)-OOH peroxo are primarily located on the surface of ferrihydrite and hematite. Selective oxidation of methyl phenyl sulfoxide and methyl phenyl sulfide to the corresponding oxidation products further reveals the presence of ≡Fe(IV)═O oxo on both ferrihydrite and hematite, and the doped Cu/Co significantly decreases the produced ≡Fe(IV)═O oxo on ferrihydrite, while increases the produced ≡Fe(IV)═O oxo on hematite. Meanwhile, selective oxidation of benzyl alcohol to benzaldehyde indicates the presence of ≡Fe(III)-OOH peroxo on both ferrihydrite and hematite, and the doped Cu/Co apparently increases the produced ≡Fe(III)-OOH peroxo on ferrihydrite and hematite. Raman analysis further reveals the presence of ≡Fe(IV)═O oxo and ≡Fe(III)-OOH peroxo on pure and metal-doped ferrihydrite/hematite, which also confirms that the doped Cu/Co decreases the produced ≡Fe(IV)═O oxo on ferrihydrite and increases ≡Fe(IV)═O oxo on hematite, while apparently increasing ≡Fe(III)-OOH peroxo on both ferrihydrite and hematite. This study enriches our understanding on the oxidizing species in the S(IV)-mediated oxidation processes under alkaline conditions, providing new insight on the oxidation reactivity of surface peroxo and oxo species mediated by the doped metal ions.
研究领域:
环境科学
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化学
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产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
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2024
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IF 5.5
Xiaomin Yan,Mingyang Zhou,Xiaofeng Gu,Xifen Gong,Jiang Liu
Hydrogen can be produced from reduction of water at the cathode of a solid oxide electrolysis cell (SOEC) and electricity and CO gas can be co-generated from the oxidation of carbon at the anode of a direct carbon solid oxide fuel cell (DC-SOFC). In the present work, a solid oxide cell (SOC) combining the cathode reaction of the SOEC and the anode reaction of the DC-SOFC is proposed, prepared, and investigated. It is demonstrated that hydrogen and CO can be separately produced from the cathode and anode through simultaneous reduction of water and oxidation of carbon in such a H 2 O-C SOC. Resistances from electrode polarizations are analyzed through measuring current-voltage characteristics, overpotentials, and AC impedances of the cell. The advantage of the H 2 O-C SOC over two separately operated SOEC and DC-SOFC is verified by the resistance analysis. An electrolyte-supported H 2 O-C SOC, with a cermet of silver and gadolinium-doped ceria (Ag-GDC) as the symmetrical electrode material and a steam concentration of 50 % at the cathode, gives an operating current density of 0.67 A cm -2 at the thermal neutral voltage (0.7 V). It stably operates at 0.2 A cm -2 under an applied voltage of only 0.16 V, producing pure hydrogen from the cathode and CO with a concentration of 88 % from the anode. The performance is significantly improved by using an anode-supported H 2 O-C SOC which gives an operating current density of 2.27 A cm -2 at the thermal neutral voltage.
研究领域:
能源科学
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电化学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
Xingyu Kang,Haibo Yu,Xiao Ma,Eryang Shang,Hong Chen,Huizhang Zhao,Jiawei Zhang,Rong Tan,Dong Wang,Hairui Fang
An efficient portable gas sensor was developed to meet the needs of air quality monitoring, for the detection of nitrogen dioxide (NO 2 ). In this study, coaxial electrospinning technology was used to synthesize porous nanofibers of indium oxide (In 2 O 3 ) composite zinc oxide (ZnO), which are recognized as special semiconductor ceramic materials. The best sample (NFs.1–6) consists of a nanoparticle-based structure with interconnected pores, in contrast to the more compact, tightly bonded nanofibers. This porous structure enhances gas adsorption capacity, improving the sensor’s performance. At 200 °C, the synthesized In 2 O 3 @ZnO (NFs.1–6) nanofibers exhibited a high response value of 171.25 and a fast response time of 5 s to 100 parts per million (ppm) NO 2 . The excellent characteristic is attributed to its uniform structure and n-n homojunction, making the response values 38 times and 98 times that of pure ZnO and pure In 2 O 3 , respectively. Building on the research findings, a smart mask was developed that incorporates the nanofiber sensor to monitor NO 2 concentrations in the air, offering an innovative approach to wearable gas sensor technology by semiconductor ceramic materials.
研究领域:
材料科学
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环境科学
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传感器技术
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DOI
高影响因子
危险品化学品经营许可证（带存储）