APPLIED SURFACE SCIENCE
·
2023
·
IF 6.7
Dehao Kong,Weirong Zhou,Jiayin Han,Yubing Gao,Yuan Gao,Liupeng Zhao,Peng Sun,Geyu Lu
Crystal facet engineering strategy is an effective way to regulate the exposed facets, which affect the ability of the surface to adsorb and react with gas molecules, ultimately enhancing the gas-sensing properties. In this work, Co 3 O 4 mesoporous nanosheets with dominant exposed {1 1 1} facets (Co 3 O 4 -60) or {1 1 2} facets (Co 3 O 4 -100) were synthesized by simply adjusting the condensation-reflux temperature. The sensing results toward toluene show that Co 3 O 4 -60 exhibited superior performance. According to the crystal structure analysis and work function calculations, the (1 1 1) facet composed of Co 2+ would adsorb more oxygen molecules, which have been proved by experimental characterization, facilitating the sensing efficiency. The results of X-ray photoelectron spectroscopy indicated that Co 3 O 4 -60 possesses a higher Co 2+ content and chemisorbed oxygen ratio (52.9%). Furthermore, Co 3 O 4 -60 has a high electrical conductivity and a minor apparent activation energy for toluene (38.75 kJ/mol). The gas sensor based on Co 3 O 4 -60 exhibited a response of 20.6 for 100 ppm toluene with rapid recovery and a detection limit of 1 ppm. Besides, other properties such as selectivity, repeatability, and humidity resistance were evaluated. This work evidences that crystal facet engineering is a practical approach to improving the gas-sensing properties of pure-phase Co 3 O 4 .
研究领域:
材料科学
·
传感器技术
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2017
·
IF 9.446
Xiaoli Jin,Chade Lv,Xin Zhou,Congmin Zhang,Qingqiang Meng,Yue Liu,Gang Chen
Oxide defect engineering in semiconductors is of growing interest and considered as an important strategy for promoting photocatalytic performance, as it enables to couple solar energy into oxygen activation. Herein, the surface oxygen vacancies are introduced into bismuth-rich Bi 4 O 5 I 2 nanosheets (Bi 4 O 5 I 2 -OV) via a facile solvothermal route. By introducing oxygen vacancies into Bi 4 O 5 I 2 , the molecule oxygen adsorption is significantly improved. More importantly, attributed to the molecular oxygen adsorption, an instantaneous surface-bulk homojunction is constructed, which facilitates the separation and transport of photogenerated charge carriers. Therefore, noticeable molecular oxygen activation and N 2 fixation are achieved in Bi 4 O 5 I 2 -OV. These findings may shed light on designing highly efficient photocatalysts and provide fresh insights into understanding the charge migration mechanism in oxygen vacancies-related photocatalytic system.
研究领域:
材料科学
·
光催化
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2021
·
IF 3.764
Jing He,Guangyu Jia,Peiwen Wu,Yingcheng Wu,Hongping Li,Linjie Lu,Zhendong Yu,ShuaiShuai Zhou,Wenshuai Zhu,Huaming Li
Recently, production of a clean sulfur-free fuel and related green chemical processes have attracted the attention of researchers. The development of efficient desulfurizers is an effective strategy to meet this demand. Herein, a facile method to successfully construct W18O49 nanoneedles (NNs) coupled with Pt species by a spontaneous redox reaction between reductive supports and oxidative platinum precursors was revealed. The closely arranged NNs hybrids with strong metal–support electron interaction and in situ-derived carbon are successfully constructed. The Pt species are stabilized on the defective W18O49 NNs surface, which accelerates the adsorption and activation of molecular oxygen. The monolithic catalyst promotes the oxidation conversion of dibenzothiophene in the process of catalytic reactive-type desulfurization. By adjusting the reaction conditions, the catalyst shows over 99.0% dibenzothiophene conversion at only 0.8% Pt loading, and the polar products can be completely removed by extraction. Also, the catalyst showed a relatively stable regeneration and reused performance.
研究领域:
材料科学
·
环境化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
·
2020
·Vol. 96
·期 2
·431-440
·
IF 2.008
Cao Ensi,Feng Yibiao,Guo Zhaoqing,Wang Huihui,Song Guoqing,Zhang Yongjia,Hao Wentao,Sun Li,Nie Zhongquan
To further improve the ethanol sensing performance of LaFeO 3 (LFO) nanoparticles, the co-doping of acceptor and donor at La and Fe sites at equal mole amount was designed to increase the oxygen adsorbing ability of the resultant nanoparticles. A series of (La,Ba)(Fe,Ti)O 3 nanoparticles, with the designed mole ratios of Ba/La (Ti/Fe) as 0, 0.25, 0.33, 0.50, and 1.0, were prepared by a citric sol–gel method. XRD confirmed the main phase of orthorhombic LFO, and the impurity phases of cubic BaTiO 3 (BTO) and orthorhombic BaCO 3 . The incorporation of Ba and Ti into the LFO lattice was verified by the increased unit cell volume of LFO upon more doping. TEM, BET, and XPS measurements indicated that the appropriate co-doping of Ba and Ti into the LFO lattice and the simultaneous existence of BTO and BaCO 3 resulted in smaller grain size, larger BET surface area, and thus higher concentration of adsorbed oxygen species than those in the pristine LFO nanoparticle. Among all (La,Ba)(Fe,Ti)O 3 sensors, the sensor based on the (La,Ba)(Fe,Ti)O 3 nanoparticles with the designed Ba/La = 0.50 exhibited the highest gas response and sensitivity toward ethanol at the prime working temperature of 132 °C, which was ascribed to the higher surface oxygen coverage contributed by the synergistic effect of co-doping and impurity phases on the number of surface active sites and oxygen adsorbing ability.
研究领域:
材料科学
·
传感器技术
✓ 已验证
产品关联
DOI
高影响因子
Green Synthesis and Catalysis
·
2020
·
IF 0
Fei Ruan,Fengfeng Li,Zhengping Dong,Qingping Ke,Yangxin Jin,Wangcheng Zhan,Minh Ngoc Ha,Jun Tang
Heteroatom-doped transition-metal oxides are potential non-noble-metal-based catalysts for the aerobic oxidation of alcohols because of the synergistic effects of their multiple active sites. However, the design of efficient heteroatom-doped transition-metal oxide catalysts is hindered by the complexity of the synergistic effects of multiple active sites. We have developed a practical strategy for fabricating nitrogen-doped MnO 2 ( N –MnO 2 ), in which nitrogen is selectively doped at interstitial sites in MnO 2 . Use of N –MnO 2 as a catalyst enabled additive-free aerobic oxidation of alcohols in > 99% yield at 30 °C. The catalytic activity of commercial MnO 2 (< 1%) was negligible. Systematic studies of a series of Mn-based oxide catalysts, namely commercial MnO 2 , MnN x O 2− x (prepared by traditional N doping by treatment with NH 3 ), and N –MnO 2 showed that N –MnO 2 with abundant interstitial nitrogen dopant (1.8 mol%) had the best catalytic activity. Mechanistic studies suggested that the introduction of interstitial nitrogen as a dopant in MnO 2 enhanced the adsorption and dissociation of oxygen on the N –MnO 2 catalyst and promoted oxidative dehydrogenation of alcohols at interstitial nitrogen and oxygen vacancy sites. In situ infrared spectroscopy showed that C–N bonds (1161 cm −1 ) were formed and broken during benzyl alcohol oxidation. This confirms the importance of interstitial nitrogen in the catalytic cycle. This work provides an alternative strategy based on interstitial nitrogen doping for designing nitrogen-doped transition-metal oxides for aerobic oxidative reactions.
研究领域:
化学
·
材料科学
✓ 已验证
DOI
BIORESOURCE TECHNOLOGY
·
2023
·
IF 11.4
Zhao Sun,Tingwei Wang,Rongjun Zhang,Hongwei Li,Yu Wu,Sam Toan,Zhiqiang Sun
Gasification is one of the most promising approaches to accomplishing efficient utilization of biomass, nevertheless, it shows severe problems of low efficiency and syngas quality, which deserves further improvements. In this regard, deoxygenation-sorption-enhanced biomass gasification is proposed and experimentally explored using deoxidizer-decarbonizer materials ( x CaO-Fe) for intensified hydrogen production . The materials follow the deoxygenated looping of Fe 0 -3e − ↔Fe 3+ as an electron donor and the decarbonized looping of CaO + CO 2 ↔ CaCO 3 as a CO 2 sorbent. Specifically, the H 2 yield and CO 2 concentration reach 7.9 mmol·g −1 biomass and 10.5 vol%, which increases by 311% and decreases by 75%, respectively, compared with conventional gasification, confirming the promotion effect of deoxygenation-sorption enhancement. Fe embedded within the CaO phase is successfully constructed with the formation of functionalized interface structure, affirming the strong interaction between CaO and Fe. This study brings in a new concept for biomass utilization via synergistic deoxygenation and decarbonization, which will substantially boost high-quality renewable hydrogen production .
研究领域:
能源与环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
SURFACE & COATINGS TECHNOLOGY
·
2022
·
IF 4.865
Shiyu Cui,Zhou Yi,Yi Xu,Jun Huang,Jilin Xu,Junming Luo,Qiong Jiang,Jiayi Peng,Xiaoma Tao
Molybdenum disilicide (MoSi 2 ) is a novel crack-healing material used in the traditional thermal barrier coating , which reacts with ZrO 2 to attain a corresponding volume expansion of approximately 138%. However, the pre-oxidation of MoSi 2 causes the “pesting” phenomenon, which degrades the microstructure and mechanical properties throughout the service. To address this issue, the aluminum oxide was fabricated on the MoSi 2 surface using the sol-gel method and low-pressure post-heat treatment to prevent oxygen penetration. The orthogonal experiment investigated the effect of pH, temperature, and water amount on sol generation. Because the Zeta potential difference has reached its maximum value (about 27 mV) at pH 4, the aluminum sol was notably adsorbed on the MoSi 2 particles. The modified MoSi 2 @Al 2 O 3 particles were characterized to understand their morphologies, surface adsorption energy, and crystal structures. The oxygen adsorption energy on the MoSi 2 (103) surface was lower than that on the Mo 5 Si 3 (411) surface, which indicated that the oxidization process can be divided into two independent steps. The Al 2 O 3 shell was uniformly formed on the MoSi 2 particles, especially in the low-vacuum environment (10 MPa) for 3 h post-treatment. The dense core-shell structure can prevent oxygen penetration into the MoSi 2 surface, thus prolonging the self-healing property of MoSi 2 .
研究领域:
材料科学
·
表面工程
·
涂层技术
✓ 已验证
DOI
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 72
·45420-45431
·
IF 3.108
Jiuli Guo,Huanhuan Yu,Feng Dong,Baolin Zhu,Weiping Huang,Shoumin Zhang
A highly efficient and stable Au–Cu/hydroxyapatite (HAP, Ca10(PO4)6(OH)2) catalyst was reported. HAP was prepared through a deposition–precipitation method. Au–Cu/HAP catalysts were obtained by a two-step impregnation approach. The samples were characterized by XRD, TEM, SEM, UV-Vis, ICP, XPS, H2-TPR, and O2-TPD. CO oxidation reaction was carried out to evaluate the catalytic performance of samples. TEM and UV-Vis results showed that the metallic particles supported on Au–Cu/HAP were smaller than those on Au/HAP, and they were highly dispersed on the HAP support. Patterns of XPS revealed that CuO nanoparticles were formed in the Cu/HAP catalyst, while CuO and Cu2O species coexisted in Au–Cu/HAP catalyst. Based on the O2-TPD data, the addition of copper to Au/HAP gave rise to more new O2 adsorption sites and bigger O2 adsorption capacity. The catalysis results indicated that the Au–Cu/HAP was capable of obtaining higher efficiency and stability compared with Au/HAP and Cu/HAP for CO oxidation. It was likely that the synergistic interaction between gold and CuOx phase created the most active sites on Au–Cu/HAP and was responsible for the enhanced activity and stability in comparison with Au/HAP and Cu/HAP.
研究领域:
催化化学
·
材料科学
·
环境化学
·
纳米催化
·
表面科学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Shiyu Liu,Rongchang Wang,Cuixiang Ma,Dianhai Yang,Duanxin Li,Zbigniew Lewandowski
Oxygen and reactive oxygen species (ROS) produced during algal photosynthesis are important electron acceptors in photosynthetic algal microbial fuel cell (PAMFC) cathodes. In this study, spongy and petaline ZnO– [email protected] carbon felt cathodes were first fabricated through in situ ZnO–NiO growth and further modified with reduced graphene oxide (rGO) via electrodeposition and cyclic voltammetry reduction. The structural and electrochemical properties of the ZnO– [email protected] carbon felt cathodes were characterized, and the ROS adsorption capacity of the cathodes was analyzed via temperature programmed desorption and UV spectrophotometry. The results illustrated that the optimal molar ratio of Zn to Ni was 0.2 for cathode surface modification, and the specific surface areas of spongy and petaline ZnO 0.2 – [email protected] reached 215.26 and 230.88 mg·g −1 , respectively, which were more than 200-fold higher than that of prefabricated carbon felt. The areal capacitance values of spongy and petaline ZnO 0.2 – [email protected] cathodes reached 3033.5 and 6388.92 mC·cm −2 , respectively. The ROS concentrations on the spongy and petaline ZnO 0.2 – [email protected] cathode surfaces reached 52.36 and 64.02 μmol·L −1 , respectively, which were nearly 2-fold higher than that for prefabricated carbon felt cathode. The power densities of PAMFCs using spongy and petaline ZnO 0.2 – [email protected] as cathode electrodes were 20.18 and 31.92 mW·m −2 , respectively. The improvement of electrochemical performance of PAMFCs is partially ascribed to the enhanced ROS adsorption capacity of ZnO– [email protected] cathodes. Therefore, ROS adsorption capacity is recommended as an evaluation indicator for PAMFC cathodes.
研究领域:
环境科学
·
电化学
·
材料科学
·
微生物燃料电池
✓ 已验证
产品关联
DOI
高影响因子
Materials Science and Engineering B-Advanced Functional Solid-State Materials
·
2025
·
IF 4.6
Guofan Wang,Tao Wang,Tanrui Xi,Yangfan Sun,Ke Wan,Qingshan Li,Yuanna Sun
The performance of intermediate-temperature solid oxide fuel cells (SOFCs) depends on cathode materials with low thermal expansion coefficients to match the electrolyte. La 0.95 Ag 0.05 CoO 3 perovskite exhibits mixed ionic-electronic conductivity and high oxygen adsorption capacity, making it a promising cathode material. However, its high thermal expansion coefficient limits compatibility with the electrolyte. This study introduces a dispersive coating approach to enhance thermal expansion compatibility. A high-activity, durable cathode is fabricated and compared with traditional Co-based cathodes. In a 100-hour R p test at 700 ℃, the coated cathode exhibits excellent stability, with only 0.4 % fluctuation over 31–50 cycles. The findings demonstrate that the dispersive coating effectively offsets the high thermal expansion of Co-containing perovskite cathodes, providing a promising strategy for developing durable, high-performance SOFCs.
研究领域:
能源材料
·
电化学
·
陶瓷材料
·
燃料电池技术
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Xinwei Zhu,Jimin Shen,Jing Kang,Pengwei Yan,Lei Yuan,Yizhen Cheng,Binyuan Wang,Shengxin Zhao,Zhonglin Chen
Developing highly efficient and anti-interference catalysts was still a challenge for the practical application of heterogeneous catalytic ozonation (HCO) in water decontamination. Herein, a magnetic Fe 3 C decorated biochar (Fe 3 C/BC) was prepared for HCO to achieve efficient degradation of 2,4-dichlorophenoxyacetic acid (2,4-D). The Fe 3 C/BC catalytic ozonation system promoted the degradation ratio of 2,4-D from 58.7% (ozonation alone) to 90.0% within 10 mins when the ozone dosage was 1.0 mg/L. And the observed degradation rate constant ( k obs ) of 2,4-D under catalytic ozonation system was 2.58 times that of ozonation alone. Fe 3 C/BC exhibited negligible adsorption on 2,4-D but with a significant enrichment to ozone, which realized the cooperating process of “adsorption-catalysis” at the solid–liquid interface, thus avoiding the ineffective decomposition of ozone. The dissociative adsorption of ozone molecules on the surface Fe 3 C generated surface atomic oxygen species (O* and O 2 *), which mediated the in-situ formation of hydroxyl radicals (·OH). ATR-FTIR, in-situ Raman, isotope tracing tests, and theoretical calculations were used to disclose the interface reaction processes and reveal the ·OH formation mechanism. Free radical reactions at the interface efficiently avoid the interference of coexisting ions dissolved in water. The presence of 3 mM (183 mg/L) bicarbonate had essentially little effect on the degradation of 2,4-D. The consecutive use of Fe 3 C/BC did not influence its catalytic performance and stable structure. This study provided new insight into the ·OH-dominated interfacial reaction in the HCO process.
研究领域:
环境科学
·
水处理
·
催化
·
高级氧化过程
✓ 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）