| 1. |
- Liu, Xueqi, et al.
(författare)
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Study on charge transportation in the layer-structured oxide composite of SOFCs
- 2018
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Ingår i: International journal of hydrogen energy. - : Elsevier. - 0360-3199 .- 1879-3487. ; 43:28, s. 12773-12781
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Tidskriftsartikel (refereegranskat)abstract
- In the past few years, triple (H+/O2-/e(-)) conducting materials have been regarded as one of the most promising electrode categories for solid oxide fuel cells (SOFCs). In this work, a layer-structured LiNi0.8Co0.15Al0.05O2-delta (LNCA) with triple conduction has been studied. The semiconductor-ionic conductor (SIC) LNCA-SDC composite has been fabricated by compositing the LNCA material with ionic conductor, i.e., samarium doped ceria (SDC). The electrochemical performance of the LNCA-SDC composite was studied by electrochemical impedance spectroscopy, while its electronic conductivity was confirmed by d.c. polarization method. It is found that the ionic conductivity of the composite is higher than the electronic conductivity by several orders of magnitude. The charge carriers and transportation properties of LNCA-SDC were studied using H+ and O2- blocking layer cells respectively. Results prove that the LNCA-SDC composite is a hybrid oxygen ion-proton conducting material. The oxygen ion conduction is dominated at low temperature (425 -500 degrees C), however, it is comparable with H+ conduction at high temperature (550 degrees C). Additionally, the formation of Li2CO3 under fuel cell operation environment was observed and the mechanism of the hybrid conductivity of LNCA-SDC was studied.
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| 2. |
- Liu, Yanyan, et al.
(författare)
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Industrial grade rare-earth triple-doped ceria applied for advanced low-temperature electrolyte layer-free fuel cells
- 2017
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Ingår i: International journal of hydrogen energy. - : PERGAMON-ELSEVIER SCIENCE LTD. - 0360-3199 .- 1879-3487. ; 42:34, s. 22273-22279
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Tidskriftsartikel (refereegranskat)abstract
- In this study, the mixed electron-ion conductive nanocomposite of the industrial-grade rare-earth material (Le(3+), Pr3+ and Nd3+ triple-doped ceria oxide, noted as LCPN) and commercial p-type semiconductor Ni0.8Co0.15Al0.05Li-oxide (hereafter referred to as NCAL) were studied and evaluated as a functional semiconductor-ionic conductor layer for the advanced low temperature solid oxide fuel cells (LT-SOFCs) in an electrolyte layer-free fuel cells (EFFCs) configuration. The enhanced electrochemical performance of the EFFCs were analyzed based on the different semiconductor-ionic compositions with various weight ratios of LCPN and NCAL. The morphology and microstructure of the raw material, as prepared LCPN as well the commercial NCAL were investigated and characterized by Xray diffraction (XRD), scanning electron microscope (SEM), and energy-dispersive X-ray spectrometer (EDS), respectively. The EFFC performances and electrochemical properties using the LCPN-NCAL layer with different weight ratios were systematically investigated. The optimal composition for the EFFC performance with 70 wt% LCPN and 30 wt% NCAL displayed a maximum power density of 1187 mW cm(-2) at 550 degrees C with an open circuit voltage (OCV) of 1.07 V. It has been found that the well-balanced electron and ion conductive phases contributed to the good fuel cell performances. This work further promotes the development of the industrial-grade rare-earth materials applying for the LTSOFC technology. It also provides an approach to utilize the natural source into the energy field.
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| 3. |
- Luo, Yifei, et al.
(författare)
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Technology Roadmap for Flexible Sensors
- 2023
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Ingår i: ACS Nano. - : American Chemical Society. - 1936-0851 .- 1936-086X. ; 17:6, s. 5211-5295
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Forskningsöversikt (refereegranskat)abstract
- Humans rely increasingly on sensors to address grand challenges and to improve quality of life in the era of digitalization and big data. For ubiquitous sensing, flexible sensors are developed to overcome the limitations of conventional rigid counterparts. Despite rapid advancement in bench-side research over the last decade, the market adoption of flexible sensors remains limited. To ease and to expedite their deployment, here, we identify bottlenecks hindering the maturation of flexible sensors and propose promising solutions. We first analyze challenges in achieving satisfactory sensing performance for real-world applications and then summarize issues in compatible sensor-biology interfaces, followed by brief discussions on powering and connecting sensor networks. Issues en route to commercialization and for sustainable growth of the sector are also analyzed, highlighting environmental concerns and emphasizing nontechnical issues such as business, regulatory, and ethical considerations. Additionally, we look at future intelligent flexible sensors. In proposing a comprehensive roadmap, we hope to steer research efforts towards common goals and to guide coordinated development strategies from disparate communities. Through such collaborative efforts, scientific breakthroughs can be made sooner and capitalized for the betterment of humanity.
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| 4. |
- Meng, Yuanjing, et al.
(författare)
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High-performance SOFC based on a novel semiconductor-ionic SrFeO3-delta-Ce0.8Sm0.2O2-delta membrane
- 2018
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Ingår i: International journal of hydrogen energy. - : Elsevier. - 0360-3199 .- 1879-3487. ; 43:28, s. 12697-12704
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Tidskriftsartikel (refereegranskat)abstract
- The semiconductor-ionic composite membrane has been recently developed for a novel solid oxide fuel cell (SOFC), i.e., the semiconductor-ion membrane fuel cell (SIMFC). In this work, the perovskite-type SrFeO3-delta (SFO) as semiconductor material was composited with ionic conductor Ce0.8Sm0.2O2-delta (SDC) to form the SFO-SDC composite membrane for SIMFCs. The SFO-SDC SIMFCs using the optimized weight ratio of 3:7 SFO-SDC membrane obtained the best performances, 780 mW cm(-2) at 550 degrees C, compared to 348 mW cm(-2) obtained from the pure SDC electrolyte fuel cell. Introduction of SFO into SDC can extend the triple phase boundary and provide more active sites for accelerating the fuel cell reactions, thus significantly enhanced the cell power output. Moreover, SFO was employed as the cathode, and a higher power output, 907 mW cm(-2) was achieved, suggesting that SFO cathode is more compatible for the SFO-SDC system in SIMFCs. This work provides an attractive strategy for the development of low temperature SOFCs.
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| 5. |
- Meng, Yuanjing, et al.
(författare)
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Low-temperature fuel cells using a composite of redox-stable perovskite oxide La0.7Sr0.3Cr0.5Fe0.5O3-delta and ionic conductor
- 2017
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Ingår i: Journal of Power Sources. - : Elsevier. - 0378-7753 .- 1873-2755. ; 366, s. 259-264
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Tidskriftsartikel (refereegranskat)abstract
- A novel solid oxide fuel cell (SOFC) incorporating the semiconductor with the ionic conductor to replace the traditional electrolyte layer with improved performance has been recently reported. In the present work, we found that the redox stable electrode material La0.7Sr0.3Cr0.5Fe0.5O3-delta(LSCrF) can be considered as a good candidate for such configuration, electrolyte layer-free fuel cells (EFFCs), due to its high ionic and electronic conductivities, excellent catalytic activity and good chemical stability. EFFCs based on the composite of perovskite oxide LSCrF and ionic conductor Ce0.8Sm0.2O2-delta (SDC) offered promising performances, i.e., 1059 mW cm(-2) at 550 degrees C without any electronic short circuiting problem. It even exhibited a highly promising result of 553 mW cm(-2) at 470 degrees C in further low-temperature operation. These high performances can be attributed to the improved conductivity, more triple-phase boundaries (TPB) and accelerated oxygen reduction reaction (ORR) of LSCrF-SDC composite. The influence of the weight ratio between LSCrF and SDC on the EFFC electrochemical performance was investigated. This new discovery indicates a great potential for exploring multifunctional perovskites for the new SOFC technologies.
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