ELECTROCHIMICA ACTA
·
2019
·
IF 5.383
Wiewei Meng,Ling Wang,Yuehua Li,Huizhu Zhou,Zhangxing He,Wei Meng,Lei Dai
CoWO 4 -PdO dual phase composites were successfully prepared by self-demixing of the precursor CoPd x WO 4+x (x = 0, 2%, 5%, 10%) calcined at 800 °C and used as sensing electrodes for mixed-potential type NH 3 sensors based on yttria stabilized-zirconia (YSZ) electrolyte. The materials were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Field-emission scanning electron microscopy (FESEM), respectively. NH 3 response performance of the sensors to different concentrations of NH 3 (20–300 ppm) was evaluated at 350–500 °C. It was found that the sensors attached with CoWO 4 -PdO sensing electrode are much more sensitive to NH 3 than the CoWO 4 -based sensor. Among them, CoWO 4 -5%PdO based sensor gives the highest sensitivity (−76.8 mV/decade at 400 °C), the response signals (Δ V ) of the sensor vary linearly with the logarithm of the NH 3 concentrations in the range of 50–300 ppm at a given temperature. The sensor also exhibits well reproducibility, stability and long-term stability. Furthermore, compared with CoWO 4 -based sensor, the introduction of PdO in CoWO 4 makes the interference of NO 2 on the sensor significantly reduced from 100% to 50%, which is attributed to the fact that the second phase PdO depresses the adsorption of NO 2 .
研究领域:
材料科学
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传感技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2024
·Vol. 171
·期 7
·077514
·
IF 3.1
Tengteng Zhao,Chaoyu Wang,Lei Dai,Weiwei Meng,Yongguang Liu,Yuehua Li,Ling Wang
NO2 is an important pollutant of automobile engines and industrial fuels, making it important to quantitatively monitor and control. An amperometric-type NO2 gas sensor was fabricated using yttria-stabilized zirconia (YSZ) electrolyte with a bi-layered structure and La0.7Sr0.3MnO3−δ-xNiO (LSMO-xNiO, x = 0–0.75) composite sensing electrode (SE) prepared by impregnation method in combination with self-demixing. The samples were characterized using SEM, XRD, and XPS, and their performance as sensors was tested. LSMO-xNiO composite SE particles were formed by de-mixing in the process of treating the precursor at high temperatures and are uniformly dispersed in the YSZ porous backbone. With the increase of NiO content, the SE particles become significantly large. At 450 °C–600 °C, the response currents at a fixed potential have a linear relationship with the NO2 concentrations at 25–700 ppm. Combining stability and sensitivity, the voltage was fixed to −0.25 V. The introduction of NiO into the LSMO sensing electrode effectively improves the performance of the sensor. The sensor based on LSMO-0.5NiO has the highest sensitivity (0.0405 μA/ppm) at 550 °C. Simultaneously, the sensor exhibits good anti-interference ability for CH4, CO2, O2, and NO, but has obvious cross-sensitivity to H2 and NH3. In addition, the response current of the sensor change with the increase of RH.
研究领域:
材料科学
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环境监测
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传感器技术
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2022
·Vol. 11
·期 4
·1785-1792
·
IF 14.511
Xin Zhou,Chenghao Yang,Caichen Yang,Jin Li,Bo Chi
The pursuit of highly reactive cathodes promotes the improvement of the electrochemical performance of solid oxide fuel cells (SOFCs), while the side reaction between the cathode and the zirconia electrolyte produces a high-resistance phase impeding interfacial ionic transport. To address this issue, we designed an unsintered composite LaCo0.6Ni0.4O3−δ-Er0.4Bi1.6O3 (LCN-ESB) cathode via self-assembly onto a Y2O3-stabilized ZrO2 (YSZ) electrolyte under in situ current polarization to fabricate a porous cathode layer and a cathode/electrolyte interface with good contact. An area-specific resistance (ASR) of 0.205 Ω cm2 and a peak power density (PPD) of 0.788 W cm−2 can be achieved by a single cell with LCN-ESB cathode at 650 °C using hydrogen as fuel, and the cell runs stably for over 100 h without severe degradation. The oxygen reduction reaction (ORR) activity of the self-assembled LCN-ESB cathode is competitive among intermediate-temperature (IT) SOFC cathodes. This work provides more possibilities for the practical application of YSZ-based SOFCs.
研究领域:
材料科学
·
能源技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2016
·
IF 3.014
Silin Li,Hengyong Tu,Feng Li,Muhammad Tuoqeer Anwar,Lijun Yu
In order to improve the performance of intermediate temperature solid oxide fuel cells (IT-SOFCs), the effect of partial substitution of the transition metal M = Co, Cu, Fe and Mn for Ni in Nd 2 NiO 4+δ on the crystal chemistry, electrical conductivity , thermal stability, chemical reactivity with YSZ electrolyte and electrochemical performance has been systematically investigated. The electrochemical performances of the cathode materials are tested on planar NiO-YSZ anode-supported cells fabricated with YSZ as electrolyte in size of 50 mm × 50 mm. Compared to Nd 2 NiO 4+δ , each Nd 2 Ni 0.9 M 0.1 O 4+δ material shows a decrease in electrical conductivity and an increase in lattice volume, oxygen vacancy concentration and chemical reactivity with YSZ electrolyte. The cell with Nd 2 Ni 0.9 Co 0.1 O 4+δ cathode achieves the maximum power density of 530 mW cm −2 at 0.7 V at 800 °C. The cell with Nd 2 Ni 0.9 Cu 0.1 O 4+δ cathode is the most stable in short-term test. A small amount of B-site doping in Nd 2 NiO 4+δ does not cause any change in the cathode microstructure. The study demonstrates that a tradeoff between oxygen transport properties and electrical conductivity can be accomplished by appropriate selection of transition metal and level of cation B-site doping in Nd2NiO4+δ. Nd2Ni0.9M0.1O4+δ (M = Co, Cu) can be considered to be potential cathode materials in IT-SOFCs.
研究领域:
材料科学
·
能源工程
✓ 已验证
产品关联
DOI
高影响因子
Crystals
·
2021
·Vol. 11
·期 12
·1573
·
IF 2.589
Xiaoqing Si,Xiaoyang Wang,Chun Li,Tong Lin,Junlei Qi,Jian Cao
Reactive air brazing has been widely used in fabricating solid oxide fuel/electrolysis cell (SOFC/SOEC) stacks. However, the conventional Ag–CuO braze can lead to (I) over oxidation at the steel interconnect interface caused by its adverse reactions with the CuO and (II) many voids caused by the hydrogen-induced decomposition of CuO. The present work demonstrates that the Ag particle interlayer can be used to join yttria-stabilized zirconia (YSZ) electrolytes to AISI 441 interconnect in air instead of Ag–CuO braze. Reliable joining between YSZ and AISI 441 can be realized at 920 °C. A dense and thin oxide layer (~2 μm) is formed at the AISI 441 interface. Additionally, an interatomic joining at the YSZ/Ag interface was observed by TEM. Obtained joints displayed a shear strength of ~86.1 MPa, 161% higher than that of the joints brazed by Ag–CuO braze (~33 MPa). After aging in reducing and oxidizing atmospheres (800 °C/300 h), joints remained tight and dense, indicating a better aging performance. This technique eliminates the CuO-induced issues, which may extend lifetimes for SOFC/SOEC stacks and other ceramic/metal joining applications.Keywords:solid oxide fuel/electrolysis cells;sintering;YSZ;Ag particle interlayer;aging
研究领域:
材料科学
·
能源工程
✓ 已验证
产品关联
DOI
高影响因子