SENSORS AND ACTUATORS B-CHEMICAL
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2020
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IF 7.1
Weiwei Meng,Ling Wang,Huizhu Zhou,Yongguang Liu,Lei Dai
Impedimetric NH 3 sensors using Yttria-stabilized zirconia (YSZ) as solid electrolyte and spinel-type oxide as sensing electrode (SE) were fabricated. Phase angle (θ) was employed as response signals to evaluate their sensing performance, as a comparison, modulus value (|Z|) response was also examined. The SE materials with nanostructure were in-situ introduced into the YSZ porous skeleton by impregnation technique. A series of spinel-type oxide MFe 2 O 4 (M = Ni, Zn and Co) were examined, and among these oxides, NiFe 2 O 4 was found to be the most excellent SE for NH 3 sensor. Sensing performance of the sensor was optimized by adjusting the loading amount and calcination temperature of the sensing material NiFe 2 O 4 and the sensor exhibits the best performance when the loading amount is 0.585 mg and the calcination temperature is 800 °C. Sensing performance of the sensor was tested in 50−1000 ppm NH 3 with temperature varying from 400 to 650 °C. Compared with modulus value (|Z|), θ as response signal improves sensing performance of NH 3 sensor. The sensor exhibits short recovery time, high sensitivity and reproducible response at 600 °C. The sensor has good anti-interference capability to CO 2 , CH 4 , H 2 , NO 2 and NO, but O 2 and relative humidity (RH) have a certain effect on sensing performance.
研究领域:
材料科学
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传感器技术
✓ 已验证
DOI
高影响因子
Nature Communications
·
2025
·Vol. 16
·期 1
·1-11
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IF 15.7
Hu Yajie,Li Puying,Lai Guobin,Lu Bing,Wang Haiyan,Cheng Huhu,Wu Mingmao,Liu Feng,Dang Zhi-Min,Qu Liangti
Line-filtering electrochemical capacitors (LFECs) are demonstrating advantages in line filtering over traditional electrolytic capacitors. However, they can only function at no-load or low-power conditions due to the limited high-frequency capacitance resulting from the excessive ionic resistance, despite much progress in electrode materials. Here, we show separators dominate both ion migration and capacitance in LFECs. A 3 μm-thick thread-anchor structured separator is developed, featuring both accelerated ionic transport and reliability, leading to a low ionic resistance of 25 mΩ cm 2 . With a phase angle of −80° at 120 Hz, the assembled device has an areal capacitance of 6.6 mF cm −2 . Furthermore, stack integration in parallel breaks the trade-off between capacitance and frequency response, boosting the areal capacitance by two orders of magnitude without decay of frequency characteristics. The On-board field test demonstrates that voltage ripples are steadily suppressed below 5% even for practical high-power line filtering with a load power density of 2.5 W cm −2 , three orders of magnitude higher than previous instances. This work opens up a perspective of separator engineering for the development of high-performance line-filtering electrochemical capacitors and promotes their applications in practical high-power scenarios.
研究领域:
电化学
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能量存储
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材料科学
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电力电子
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应用物理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Yongjian Chen,Xiankan Zeng,Cheng Yan,Shiyu Yang,Lunyao Pan,Chenglong Li,Maolin Mu,Wen Li,Guanqi Tang,Weiqing Yang
Charge carriers will recombine outside the emitting layer (EML) in non-ideal perovskite light-emitting diodes (PeLEDs), which can lead to parasitic loss and be detrimental to the performance of PeLEDs. Here, we have subtly utilized the property of perovskite nanocrystals (NCs) to design and optimize the homogeneity and optical property of EML, thereby suppressing the undesired carrier loss behavior in system. Photoluminescence (PL) spectra with transmission electron microscopy (TEM) images show that smaller and more homogeneous NCs in size are obtained by temperature-controlled (TC) method. Atomic force microscopy (AFM) images and temperature-dependent PL spectra show that EML with better optical property and uniformity is fabricated. The multiscale capacitance characterization shows that the device with modified EML exhibits significantly reduced leakage current, while the increased specific surface area between electron transport layer (ETL) and EML substantially reduces charge accumulation. Additionally, multiscale reactance, impedance and phase angle responses, reveal that the carrier oscillation behavior in the optimized device is suppressed compared to control group, leading to less energy loss. Consequently, the optimized devices exhibit lower leakage current and superior electroluminescent properties. The luminance is increased from 31650 cd/m 2 to 72941 cd/m 2 , current efficiency (CE) is improved from 59.9 cd/A to 94.3 cd/A, and the external quantum efficiency (EQE) rises from 12.6 % to 19.7 %, corresponding to improvement of 230 %, 157 %, and 156 %, respectively. This research provides valuable insight into the impact of functional layer morphology on carrier dynamic behavior in PeLEDs.
研究领域:
材料科学
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光电技术
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纳米技术
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半导体物理
✓ 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）