Energy Advances
·
2024
·
IF 3.2
Yi Zheng,Hongyu Zheng,Yuanchong Yue,Liying Lu,Yingli Wang,Qunwei Tang
Harnessing waste green energy utilizing advanced energy conversion technologies is widely considered a promising avenue for enhancing the power generation capacity of renewable energy. In this study, we present the experimental realization of a tailored energy conversion device using graphene-carbon black/polyvinyl chloride (G-CB/PVC) composite films for the innovative harvesting of rainwater energy. Based on the cyclic charge–discharge behaviors of electron/cationic pseudocapacitance at the film–raindrop interface, periodic current and voltage signals were generated with maximum values exceeding 2.5 μA and 100 μV per droplet by optimizing the concentrations and species of cations, respectively. Electricity outputs were significantly enhanced by increasing the electron concentration in the composite films. It is noteworthy that rainwater energy-harvesting devices exhibit exceptional long-term stability, enduring persistent attacks posed by continuous simulated rainfall conditions.
研究领域:
材料科学
·
能源技术
✓ 已验证
DOI
高影响因子
INTERMETALLICS
·
2025
·
IF 4.8
Liangcai Du,Xiaoqing Liu,Qianqian Kong,Lichao Gong,Zhenhua Yao
Understanding the intricate phase transformations and their impact on the mechanical properties holds paramount importance in developing high entropy alloys (HEAs) with ideal properties, yet it remains challenging and underexplored. In this study, a series of novel CrFeMnNi (2-x) Ti x (x = 0, 0.5, 1, and 1.5 at.%) HEAs were meticulously designed based on the established Valence Electron Concentration (VEC) rule, with the VEC values systematically varied as the atomic composition (Ni, Ti) changed. The microstructure, phase transformation behavior, mechanical properties, and strengthening mechanisms were systematically investigated. We found that the HEA powders exhibited phase behavior consistent with the VEC rules. The spark plasma sintered (SPSed) HEA bulk samples exhibited a phase transformation attributed to the precipitation of Cr and Mn within the matrix, resulting in the formation of the σ phase. Quantitative calculation of the strengthening mechanisms revealed that grain boundary strengthening and precipitation strengthening were the primary contributors to the high strength of the HEA bulk samples. These findings not only advance the utilization of the VEC rules in HEA material design but also contribute to the understanding of the phase behavior and mechanical properties of HEAs, facilitating the design of high performance HEAs.
研究领域:
材料科学
·
冶金学
·
机械工程
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2021
·Vol. 56
·期 22
·12732-12739
·
IF 4.22
Li Yuping,Huo Haojie,Huang Hai,Guo Kai,Yang Xinxin,Xing Juanjuan,Luo Jun,Rao Guang-Hui,Zhao Jing-Tai
Layered oxygen-containing compound Bi 2 O 2 Se is a promising n-type thermoelectric material, favored by its considerably high Seebeck coefficient and low thermal conductivity. Significant preferred orientation along plane (110), identified in the hot-pressed sample, results in obvious anisotropy in the electrical and thermal transport properties. Nb substitution Bi in the insulating layer [Bi 2 O 2 ] 2+ can effectively increase the electron concentration (from 10 16 to 10 18 cm −3 ) by two orders of magnitude, while maintaining high mobility. Therefore, a larger power factor of 2.19 μW cm −1 K −2 has been obtained for Bi 1.94 Nb 0.06 O 2 Se at 823 K, which enlarges by three times in comparison with pristine Bi 2 O 2 Se (0.673 μW cm −1 K −2 ). Combined with the inherently low thermal conductivity, the ZT values of Bi 1.94 Nb 0.06 O 2 Se reach 0.195 at 823 K, corresponding to 325% enhancement. This study shows that the substitution of Nb for Bi is a promising way to optimize the thermoelectric properties of Bi 2 O 2 Se-based thermoelectric materials.
研究领域:
材料科学
·
热电学
·
固体物理学
✓ 已验证
DOI
高影响因子
DALTON TRANSACTIONS
·
2018
·Vol. 47
·期 11
·3819-3830
·
IF 4.099
Karim Khan,Ayesha Khan Tareen,Sayed Elshahat,Ashish Yadav,Usman Khan,Minghui Yang,Luigi Bibbò,Zhengbiao Ouyang
One of the greatest challenges in the enhancement of the electrical properties of conductive mayenite [Ca24Al28O64]4+(4e−) (hereinafter C12A7:e−) is the design of a more suitable/simple synthesis strategy that can be employed to obtain the required properties such as excellent stable electrical conductivity, a high electron concentration, outstanding mobility, and an exceptionally large surface area. Therefore, to synthesize C12A7:e− in the metallic state, we proposed a facile, direct synthesis strategy based on an optimized sol–gel combustion method under a nitrogen gas environment using the low-cost precursors Ca(NO3)2·4H2O and Al(NO3)3·9H2O. Using this developed strategy, we successfully synthesized moderately conductive nanoscale C12A7:e− powder, but with unexpected carbon components (reduced graphene oxide (rGO) and/or graphene oxide (GO)). The synthesized C12A7:e− composite at room temperature has an electrical conductivity of about 21 S cm−1, a high electron concentration of approximately 1.5 × 1021 cm−3, and a maximum specific surface area of 265 m2 g−1. Probably, the synthesized rGO was coated on nanocage C12A7:e− particles. In general, the C12A7:e− electride is sensitive to the environment (especially to oxygen and moisture) and protected by an rGO coating on C12A7:e− particles, which also enhances the mobility and keeps the conductivity of C12A7:e− electride stable over a long period. Doped mayenite electride exhibits a conductivity that is strongly dependent on the substitution level. The conductivity of gallium-doped mayenite electride increases with the doping level and has a maximum value of 270 S cm−1, which for the first time has been reported for the stable C12A7:e− electride. In the case of Si-substituted calcium aluminate, the conductivity has a maximum value of 222 S cm−1 at room temperature.
研究领域:
无机化学
·
材料科学
·
纳米材料
·
固态化学
·
电化学
·
功能材料
✓ 已验证
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2022
·
IF 9.221
Liupeng Zhao,Yiwen Li,Yue Zhou,Tianshuang Wang,Peng Sun,Fangmeng Liu,Chenguang Wang,Xu Yan,Nianke Chen,Geyu Lu
The effect of high- and low-valence doping on adsorbed oxygen has been studied and intensely discussed for decades, in which the high-valence dopant can provide more electrons for ionosorbed oxygen species while low-valence dopant can provide more adsorption sites. In this work, this effect is observed directly by Quasi in-situ X-ray photoelectron spectroscopy and CO temperature-programmed reduction, and rationalized by density functional theory calculations. It is found that the oxygen vacancies can be easier to generate on Co-doped SnO 2 surface, but the decrease in surface electron concentration actually reduces the amount of adsorbed oxygen at working temperature while Sb-doped SnO 2 is more conducive to oxygen adsorption but the enormous electron concentration makes the resistance variation caused by the surface reactions insignificant. In order to combine the advantages of both dopants, Sb-doped SnO 2 @Co-doped SnO 2 core-shell structure are designed and prepared. The synergism of the core and shell can enhance sensing reactions on the surface while efficiently converting the surface reactions into a resistance change. On the one hand, the electron diffusion from the electron-rich core to the shell provides the electrons required for oxygen adsorption, which ensures sufficient surface reactions. On the other hand, a potential barrier is formed between the core and shell which can regulate electron transport between adjacent cores, thereby effectively converting the surface reaction into a resistance change.
研究领域:
材料科学
·
表面科学
·
计算化学
✓ 已验证
DOI
高影响因子
ADVANCED MATERIALS
·
2024
·Vol. 36
·期 31
·2403792
·
IF 27.4
Kaiyang Xu,Lecheng Liang,Tong Li,Mujie Bao,Zhipeng Yu,Jingwei Wang,Sitaramanjaneya Mouli Thalluri,Fei Lin,Quanbing Liu,Zhiming Cui,Shuqin Song,Lifeng Liu
Seawater electrolysis is a potentially cost-effective approach to green hydrogen production, but it currently faces substantial challenges for its high energy consumption and the interference of chlorine evolution reaction (ClER). Replacing the energy-demanding oxygen evolution reaction with methanol oxidation reaction (MOR) represents a promising alternative, as MOR occurs at a significantly low anodic potential, which cannot only reduce the voltage needed for electrolysis but also completely circumvents ClER. To this end, developing high-performance MOR catalysts is a key. Herein, a novel quaternary Pt 1.8 Pd 0.2 CuGa/C intermetallic nanoparticle (i-NP) catalyst is reported, which shows a high mass activity (11.13 A mg PGM −1 ), a large specific activity (18.13 mA cm PGM −2 ), and outstanding stability toward alkaline MOR. Advanced characterization and density functional theory calculations reveal that the introduction of atomically distributed Pd in Pt 2 CuGa intermetallic markedly promotes the oxidation of key reaction intermediates by enriching electron concentration around Pt sites, resulting in weak adsorption of carbon-containing intermediates and favorable adsorption of synergistic OH − groups near Pd sites. MOR-assisted seawater electrolysis is demonstrated, which continuously operates under 1.23 V for 240 h in simulated seawater and 120 h in natural seawater without notable degradation.
研究领域:
材料科学
·
催化
·
电化学
·
可再生能源
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）