JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
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2020
·Vol. 96
·期 2
·431-440
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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
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传感器技术
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产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2023
·Vol. 11
·期 40
·21645-21654
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IF 11.9
Min Zhang,Zhihong Du,Zhipeng Sun,Hailei Zhao
Iron-based double perovskites, as mixed electronic and oxygen ionic conductors, are potential air electrodes for reversible solid fuel cells. However, their catalytic activity towards the oxygen reduction reaction/oxygen evolution reaction is inferior to that of cobalt-based perovskites. Herein, a BaCO3-infiltrated SmBaFe2O5+δ (SBF) electrode is proposed with significantly enhanced catalytic activity. The theoretical computation and experimental study demonstrate that BaCO3 can significantly accelerate the oxygen adsorption/dissociation kinetics, which is identified to be the rate-limiting step of the SBF electrode. The BaCO3 decoration decreases significantly the polarization resistance from 0.154 to 0.068 Ω cm2 at 700 °C in air, and enables superior electrochemical performance in both fuel cell (FC) and electrolysis cell (EC) modes. The single cell with BaCO3 infiltrated SBF as an air electrode exhibits good operational stability in a reversible FC/EC mode for 34 cycles at ±300 mA cm−2, manifesting the good structural stability of the BaCO3-infiltrated SBF composite electrode under redox conditions. This work highlights the importance of clarifying the rate-limiting step and finding an effective strategy to facilitate this specific process for the design of high performance electrode materials.
研究领域:
材料科学
·
能源科学
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DOI
高影响因子
Journal of Cleaner Production
·
2024
·
IF 9.7
Wentao Li,Qian Zhang,Zuohua Liu,Changyuan Tao,Guocan Zheng,Dong Wang,Hufei Chen
Long-term accumulation of manganese sulfate residue can lead to the release of soluble manganese ions, which in turn can contaminate the surrounding environment. However, effectively guiding the treatment of soluble manganese in manganese sulfate residue is challenging due to limited understanding of its metastable structure. In this study, the metastable phase of manganese sulfate residue was analyzed by transmission electron microscope (TEM), cross-reaction X-ray energy dispersive spectroscopy (EDS) and X-ray diffractometer (XRD). The results reveal that the metastable phase within manganese sulfate residue consists of amorphous hydroxide and calcium sulfate. Furthermore, the amorphous hydroxide colloid is coated by calcium sulfate. The reconstruction of the metastable structural phase in manganese sulfate residue was achieved by adding BaCO 3 . The toxic leaching of the residue after phase reconstruction was assessed. The results show that the lowest leaching concentration of Mn and Ba were 0.6737 mg L −1 and 1.778 mg L −1 , respectively. The leaching amounts of Mn and Ba were within the allowable range of GB 8978–1996 and GB 5085.3–2007, respectively. This suggests that the addition of BaCO 3 can achieve harmless of manganese sulfate residue. Finally, the reconstructed residue is used to prepare the unfired brick with wave-absorbing. The obtained results show that the compressive strength of the brick is 17.00 MPa, meeting the standard of MU15. Additionally, the minimum reflection loss value of the brick is −10.51 dB, showing that the material has promising ability in absorbing wave.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2015
·
IF 2.947
Chuande Huang,Xiaodong Wang,Xin Liu,Ming Tian,Tao Zhang
In this paper, the phase evolution, microstructure changes, and element diffusion for the formation of BaSnO 3 from BaCO 3 and SnO 2 were extensively investigated. It was found that BaCO 3 rapidly diffused on surface of SnO 2 at the initial stage of the reaction (approximately 700 °C), forming a uniform BaSnO 3 shell. Subsequently, BaSnO 3 grew via two different routes depending on the calcination temperature. When the reaction was carried out below 820 °C, BaSnO 3 phase further grew by diffusion of barium ions across BaSnO 3 layer to SnO 2 phase, since the BaSnO 3 interlayer prevented the direct reaction between surface BaCO 3 and SnO 2 core. Once a higher temperature above 820 °C was provided, Ba 2 SnO 4 were generated by reaction between BaCO 3 and BaSnO 3 shell. Under such circumstances, pure BaSnO 3 was obtained by diffusion of barium ions from Ba 2 SnO 4 across BaSnO 3 to SnO 2 . The rate-determining step in both cases was assigned to the diffusion of barium ions.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
Molecular Catalysis
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2022
·
IF 5.089
Kexin Li,Hao Li,Shuang Wei,Yumei Liu,Yingwei Li,Ruirui Zhang,Ruixia Liu
BaCO 3 -CeO 2 composite catalysts were prepared by the hydrothermal synthesis method, and the influence of Ba/Ce on the structural and catalytic performance for selective oxidation of cyclohexane with molecule oxygen was studied. The characterization results exhibited that the doping amount of BaCO 3 would influence the morphology, the content of surface Ce 3+ and surface oxygen species (O β ), and alkalinity. Meanwhile, the amount of alkali is the key to the decomposition of cyclohexyl hydrogen peroxide (CHHP). 10.5% conversion of cyclohexane and 85.0% selectivity of KA oil were achieved under the reaction conditions of 1.0 MPa O 2 and 150 °C for 2 h. The excellent catalytic activity was attributed to its high atomic ratios of Ce 3+ /Ce total and O β /O total on the surface and optimal redox capacity.
研究领域:
催化化学
·
材料科学
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产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2024
·
IF 5.8
Mingfei Yu,Xiangyu Kong,Jianhui Luo,Hanqiang Zhou,Yanxin Gao,Chenghui Zheng,Qiaoshan Chen,Jinhong Bi
The semiconductor-insulator heterostructure, characterized by outstanding economic-efficiency and catalytic activity, represents a promising photocatalyst for practical pollutants degradation. However, achieving energy band matching between semiconductors and insulators remains a challenge. In this study, we meticulously designed and synthesized a band-matched semiconductor-insulator photocatalysts (AgI-BaCO 3 ), leveraging the in-situ nucleation of ultrafine AgI nanoparticles on BaCO 3 surface. The finely crafted heterostructure notably enhanced degradation efficiency of tetracycline over both pure AgI and BaCO 3 , demonstrating a remarkable pseudo-first-order kinetic rate constant that surpassed them by 27.2 and 33.5 times, respectively. The density functional theory calculations uncovered that the intense covalent interaction between AgI and BaCO 3 established a specific channel for interfacial charge carriers. The generated CO 3 ·- radicals as the main active species markedly expedited the removal of antibiotics. Furthermore, the catalysts demonstrated robust activity in real wastewater and surface water. This work supplies a novel reference for constructing insulator-based photocatalysts and elucidates its potential application in actual aquatic environments.
研究领域:
环境科学
·
材料科学
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产品关联
DOI
高影响因子
CEMENT & CONCRETE COMPOSITES
·
2026
·
IF 14.4
Guokun Yang,Chuanlin Que,Junhui Kou,Yiye Lv,Jiuyuan Wang,Bo Qu,Rongyan Long,Guosheng Jiang,Tianle Liu
BaCO 3 -shelled phase change microcapsules improve sulfate resistance of cement paste. • The BaCO 3 shell immobilizes sulfate ions through in-situ ion exchange. • BMPCM regulates sulfate-attack products and pore-network deterioration. • Optimal BMPCM dosage reduces eroded area by 69.9% and enhances strength. Sulfate attack is one of the major degradation mechanisms responsible for expansion cracking, surface spalling, and long-term performance deterioration of cementitious materials. To improve the durability of cementitious materials in sulfate environments, a functional microcapsule (BMPCM) with a BaCO 3 shell and tetradecane core was prepared, and its effect on sulfate resistance was systematically evaluated. Cement paste specimens incorporating different BMPCM dosages were separately immersed in deionized water and MgSO 4 solution for up to 360 d. The deterioration behavior and underlying mechanisms of cement paste incorporating BMPCM were elucidated at multiple scales through macroscopic damage characterization, microstructural observation, hydration/sulfate-attack product analysis, pore connectivity assessment, and compressive strength testing. Results showed that the BaCO 3 shell reacted with invading SO 4 2− to form insoluble BaSO 4 , thereby chemically immobilizing sulfate ions. This process reduced the effective sulfate activity within the matrix, suppressed the formation of expansive products such as gypsum and ettringite, and mitigated the leaching of soluble hydration products such as Ca(OH) 2 . Compared with controls, specimens with an appropriate BMPCM dosage exhibited a 69.9% reduction in the severely deteriorated area, a 24.4% decrease in interconnected porosity, and a 44.9% increase in compressive strength after 360 d. In contrast, excessive BMPCM incorporation promoted microcapsule agglomeration and introduced initial defects, thereby weakening sulfate resistance. In addition, thermal analysis confirmed that BMPCM retained its phase-change response near the freezing point, suggesting its potential for further application in sulfate-resistant cementitious materials exposed to complex temperature-fluctuation service environments.
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DOI
高影响因子
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