THIN SOLID FILMS
·
2018
·
IF 1.939
Yanqi Lv,Yanhong Li,Hongxia Sun,Yi Guo,Yanmei Li,Jinkun Tan,Xingfu Zhou
Crystalline yttrium-doped rutile TiO 2 nanorod arrays were synthesized and successfully implemented as a photoanode of perovskite solar cells . Study shows that yttrium was successfully doped and TiO 2 band gap changes from 3.07 eV to 3.02 eV. A positive shift of 100 mV in the flat-band potential (V fb ) was observed in Y-doped rutile TiO 2 nanorods. A power conversion efficiency of 7.95% and a photocurrent density of 15.13 mA/cm 2 were obtained for the doped sample. The photocurrent density is 1.47 times higher than that of the un-doped device. Incident photon-to-current conversion efficiency shows Y-doped device has a clear increase in quantum efficiency in the visible light range from 450 and 750 nm. Open circuit voltage decay measurements demonstrate the superior ability of Y-doped TiO 2 nanorod for separating electrons and holes and decreasing the recombination events. The improved performance is possibly attributed to the enhanced electron injection and transfer efficiency caused by a positive shift in V fb and a reduction in charge recombination. This study opens a door toward the improvement of photocurrent density of perovskite solar cell via an element doping route.
研究领域:
材料科学
·
纳米科技
·
能源化学
·
光电子学
·
半导体物理
·
可再生能源
✓ 已验证
DOI
高影响因子
Small Methods
·
2024
·Vol. 8
·期 7
·2301233
·
IF 10.7
Xiaolin Ye,Ningxin Xiong,Shaopei Huang,Qixing Wu,Hongning Chen,Xuelong Zhou
Tin-based hybrid flow batteries have demonstrated dendrite-free morphology and superior performance in terms of cycle life and energy density. However, the quick accumulation of electrodeposits near the electrode/membrane interface blocks the ion transport pathway during the charging of the battery, resulting to a very limited areal capacity (especially at high current density) that significantly hinders its deployment in long-duration storage applications. Herein, a conductivity-activity dual-gradient design is disclosed by electrically passivating the carbon felt near the membrane/electrode interface and chemically activating the carbon felt near the electrode/current collector interface. In consequence, the tin metals are preferentially plated at the region near electrode/current collector, preventing the ion transport pathway from being easily blocked. The resultant gradient electrode demonstrated an unprecedentedly high areal capacity of 268 mAh cm −2 at a current density of as high as 80 mA cm −2 . Numerical modeling and experimental characterizations show that the dual-gradient electrode differs from conventional electrodes with regard to their reaction current density distribution and electrodeposit distribution during charging. This work demonstrates a new design strategy of 3D electrodes for hybrid flow batteries to induce a desirable distribution of electrodeposits and achieve a high areal capacity at commercially relevant current densities.
研究领域:
电化学储能
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材料科学
·
能源化学
·
电池技术
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功能材料
·
电化学工程
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
·
2020
·Vol. 45
·期 4
·5841-5851
·
IF 3.741
Zhi Ming Wang,Peng Liu,Yan Peng Cao,Feng Ye,Chao Xu,Xiao Ze Du
Summary In this study, novel Pt-IrO 2 nanofiber catalysts for oxygen evolution reaction (OER) were successfully prepared using the electrospinning method with a high-concentration precursor solution. The composition and structure of catalysts were characterized, and the electrocatalytic performance of the nanofiber catalysts in water electrolysis was investigated from various aspects such as overpotential, charge transfer resistance, and exchange current density. Special attention was paid on the effect of Pt/Ir ratio on the electrocatalytic activity of the electrospun nanofibers. The results showed that the Pt-IrO 2 nanofiber catalysts with average fiber diameters ranging from 10 to 100 nm can be successfully obtained by the electrospinning method, and the average diameter decreased with the increase of Pt content. Since a bigger amount of IrO 2 content and a thinner fiber structure are all beneficial to the electrocatalytic performance, the Pt-IrO 2 catalysts with Pt:Ir = 1:9 and Pt:Ir = 9:1 both showed better catalytic performance for OER than the commercial IrO 2 , which was also demonstrated by the lower charge transfer resistance and higher exchange current density. As a result, the overpotentials of Pt-IrO 2 catalysts with Pt:Ir = 1:9 and Pt:Ir = 9:1 are 50 mV and 32 mV lower than the overpotential of the commercial IrO 2 at 30 mA cm −2 in 0.5 M H 2 SO 4 , respectively. The electrospun Pt-IrO 2 nanofiber catalyst with proper Pt content seems to be very promising since it can not only improve the catalytic performance and the safety of PEM electrolysis cells, but also reduce the amount of more expensive Ir in catalysts.
研究领域:
材料科学
·
电化学
·
纳米材料
·
能源化学
·
催化化学
✓ 已验证
DOI
高影响因子
RARE METALS
·
2019
·Vol. 38
·期 6
·588-600
·
IF 1.785
Huang Lei,Su Kun,Zheng Yu-Feng,Yeung Kelvin Wai-Kwok,Liu Xiang-Mei
A TiO 2 nanofilm was prepared on the surface of AZ31 magnesium alloy with controllable thickness through atomic layer deposition (ALD) technique, which can adjust the corrosion behaviors of AZ31 Mg alloy. Compared with the untreated Mg alloys, corrosion current densities ( i corr ) can decline by 58% in the 200-cycles TiO 2 -covered Mg alloy and further decline by up to 74% with the thickness of nanofilm up to 63 nm (400 cycles). The subsequent modification with a cross-linked conversion layer of 3-amino-propyltriethoxysilane (APTES) by a dipping method can produce a compact silane coating on TiO 2 nanofilm, which can seal pinholes of TiO 2 nanofilm and serve as a barrier to further adjust the corrosion behavior of the substrate. The i corr can decline about two orders of magnitude in the TiO 2 /silane composite coating. Making the adjustable corrosion rate come true, which can be attributed to the precise control on the thickness of metal oxide nanofilm and additional protection from the compact silane coating. In vitro study discloses that the TiO 2 /silane hybrid coating shows higher expression of alkaline phosphatase (ALP) and can promote cellular adhesion and proliferation with better cytocompatibility than untreated Mg alloy.
研究领域:
材料科学
·
生物医学工程
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腐蚀科学
·
表面工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2018
·
IF 6.578
Junbin Liao,Jiajie Zhu,Shanshan Yang,Nengxiu Pan,Xinyan Yu,Chao Wang,Jun Li,Jiangnan Shen
Developing highly ion conductive and desirable electrodialysis (ED) performance anion exchange membranes (AEMs) is of great significance. In this work, we report a strategy for fabricating novel AEMs based on a series of fluoro-methyl poly(arylene ether ketone)s having long-side-chain imidazolium groups for ED. Having hydrophilic conductive flexible side-chain imidazolium groups and rigid hydrophobic backbone within AEM matrix, the optimized AEM (PAEK-60-im) shows low water uptake of 24.9% at 80 °C and desirable ion conductivity of 22.01 mS cm –1 at 30 °C. In NaCl removal application of ED, PAEK-60-im shows the NaCl removal ratio of 69.66% within 120 min, outperforming commercial AEM-Type II (68.98%). Accordingly, it has a higher current efficiency of 83.7% but lower energy consumption of 5.9 kWh kg –1 , compared with the commercial one (82.0%; 6.6 kWh kg –1 ). In particular, in selectrodialysis application, possibly owing to the synergistic effect of pore-size sieving effect resulting from macro-separation morphology and hydration energy difference of SO 4 2– ions (–1000 kJ mol –1 ) and Cl – ions (–317 kJ mol –1 ) in feeding solution, PAEK-60-im shows significantly superior monovalent anion perm-selectivity (Cl − /SO 4 2− ) of 7.70 at 30 min, relative to commercial anion-selective Neosepta ACS (5.27) and many other reported mono-valent anion selective AEMs having elegant surface modified layers. The superior ED performance of the homogeneous PAEK-60-im is suggestive of its potential separation application.
研究领域:
材料科学
·
化学工程
·
电化学
·
膜技术
✓ 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）