APPLIED SURFACE SCIENCE
·
2017
·
IF 3.387
Jiajie Yu,Muzhong Shen,Siyu Liu,Feng Li,Dongping Sun,Tianhe Wang
In this paper, we describe a simple technique for direct growth of gold nanoparticles (GNPs) into a nanostructured porous alumina layer on conductive glass slide (PAOCG). PAOCG was attached firmly with a small piece of steel and was then immersed in a HAuCl 4 solution. Electro-induced electrons from steel were employed to reduce AuCl 4 − on PAOCG. The galvanic replacement reaction (GRR) was adopted as the fundamental mechanism for reducing metal precursors. This mechanism was further studied by open circuit potential-time (OCP-t) experiment and the result demonstrated that steel induced the continuous proceeding of this reaction. This strategy presents a simple and general protocol for preparation of metal nanoparticles (MNPs) on conductive glass substrates. The SERS properties of Au/PAOCG were investigated using aqueous crystal violet (CV) and 4-mercaptopyridine (4-Mpy) as probe molecules. Au/PAOCG allowed as low as 10 −9 M CV and 10 −8 M 4-Mpy to be detected. The reusability of this substrate was achieved by measuring the SERS spectrum of the probe molecules followed with a 400 °C heat treatment for 10 min to remove the residuals. This substrate could be reused for at least ten cycles without any significantly reduced SERS performance. Therefore, this surface can serve as a portable, durable and reusable SERS substrate and has a potential for commercial applications.
研究领域:
材料科学
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分析化学
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纳米技术
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生物传感
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表面科学
✓ 已验证
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2022
·Vol. 10
·期 6
·108837
·
IF 7.968
Yumei Jian,Ye Meng,Jie Li,Hongguo Wu,Shunmugavel Saravanamurugan,Hu Li
Photocatalytic reductive conversion of bio-derivatives to biofuels and fine chemicals is an eco-friendly and energy-saving way for biomass valorization. Herein, we developed a new and high-performance protocol for control of activity/selectivity in photocatalytic reductive upgrading of biomass to biofuels at room temperature via engineering oxygen vacancy (Ov) and manipulating the exposed crystal surfaces of the TiO 2 -based catalysts, such as efficient cascade photocatalytic hydrogenation-cyclization of ethyl levulinate to γ-valerolactone in water (up to 96% yield, TOF: 112.1 h −1 ), and the selective conversion of 5-methylfurfural to 5-methylfurfuryl alcohol (90% yield) or long carbon-chain coupling products (86% yield) in methanol, respectively. The {101} crystal plane is prone to produce more Ov in situ than the {001} and {110} crystal planes. The formation of Ov was not only beneficial to the adsorption and activation of the bio-based carbonyls, but also could enhance the migration efficiency of the photo-generated carriers and effectively adjust the semiconductor band structure of the TiO 2 -based photocatalyst to promote the visible-light absorption, thus enhancing the overall reductive conversion process, as elucidated by DFT calculations. Also, the charge distribution and adsorption intensity of different exposed crystal surfaces of the photocatalyst were able to control the selectivity of the bioproducts . In addition, the optimal Ov-TiO 2− x {101} catalyst had excellent reusability and could be reused at least five times with no obvious decrease in photocatalytic performance. The strategy of selectivity control via engineering the catalyst exposed crystal surfaces and loaded Ov provides an opportunity for multi-catalytic biomass conversion to biofuels.
研究领域:
催化化学
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材料科学
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能源化学
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环境科学
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绿色化学
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表面科学
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光催化
✓ 已验证
DOI
高影响因子
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
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纳米科技
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能源化学
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光电子学
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半导体物理
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可再生能源
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2017
·
IF 3.133
Xiangyang Zhuang,Yao Zhang,Lingxiao He,Yunfeng Zhu,Quan Shi,Quan Wang,Guanzhou Song,Xiaoxiao Yan,Liquan Li
Overheating caused by exothermic effect of magnesiothermic reduction reaction is usually considered as a drawback in preparing porous silicon anode materials for Li-ion batteries. However, in the present work, thermal effect is available in facile preparation of macroporous Si by tabletting pretreatment . The released heat in magnesiothermic reaction is easily accumulated on the tablet with high density, leading to the collapse of the mesoporous structure of the precursor and formation of uniform macroporous silicon . Such macroporous silicon shows a higher initial Coulomb efficiency (86.5%) and enhanced cycling stability in comparison with mesoporous silicon prepared without tabletting treatment. XRD analysis indicates that the reaction temperature decreases to 430–435 °C (based on set temperature), much lower than that of the reaction without pretreatment. Since the structure of product has less dependency on precursor, a wide variety of precursors can be used to synthesize macroporous silicon, e.g. low cost biosilica. Being ascribed to low reaction temperature, heating rate insensitivity, less dependency on precursor, enhanced cycling performance and high initial Coulomb efficiency of the Si products, the modified magnesiothermic reduction method is promising for application in fabricating Si anode.
研究领域:
材料科学
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电化学
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纳米科技
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能源存储
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无机合成
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功能材料
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电池技术
✓ 已验证
DOI
高影响因子
COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
·
2017
·
IF 4.075
Guangshun Wu,Lei Chen,Li Liu
Effects of silane and silica enrichment of carbon fibers (CFs) on interfacial properties of methylphenylsilicone resin (MPSR) composites were investigated. CFs were oxidized, grafted with 3-aminopropyltriethoxysilane (APS) and then modified with silica nanoparticles prepared by the sol-gel polymerization of tetraethoxysilane (TEOS). Chemical structures of CFs were characterized by confirming the successful grafting. Scanning electron microscopy (SEM) showed a uniform distribution of silica nanoparticles on the CFs surface. The interlaminar shear strength (ILSS) and impact toughness of silanized CF (CF-Siloxane) composites were 12.05% and 7.46% higher than those of untreated composites. However, ILSS and impact toughness of the hybrid fiber (CF/Si) composites obtained from the hydrolysis of different concentrations TEOS improved significantly, especially for grafting silica enrichment with the TEOS concentration of 0.05 mol/L (CF/Si0.05), increasing 45.64% in ILSS and 29.59% in impact properties. Moreover, the hydrothermal aging resistance was also improved greatly. Meanwhile, functionalization processes did not decrease fiber tensile strength .
研究领域:
复合材料科学
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高分子材料
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表面改性
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界面工程
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材料化学
✓ 已验证
DOI
高影响因子
Materials Science & Engineering C-Materials for Biological Applications
·
2021
·
IF 7.328
Hongyuan Zhao,Bo Li,Runqiang Liu,Yuqi Chang,Hongliang Wang,Lin Zhou,Sridhar Komarneni
Herein, a cost-effective and scalable ultrasound assisted approach was proposed to prepare the nanocomposite of halloysite nanotubes/zirconia/carbon black (Hal/ZrO 2 /CB), which was used to fabricate a novel electrochemical sensor for the highly sensitive determination of methyl parathion (MP). In the Hal/ZrO 2 /CB nanocomposite, Hal with large specific surface area and numerous active sites could enhance the adsorption capacity and accelerate the redox reaction of MP; ZrO 2 nanoparticles with high affinity toward the phosphate group could contribute to good recognition performance for MP; CB nanoparticles with good dispersibility formed an interconnected pearl-chain-like conductive network. Benefitting from the synergistic effect of the three components, the Hal/ZrO 2 /CB/GCE (glassy carbon electrode) sensor showed a remarkably low detection limit of 5.23 nM in a good linear MP detection range of 0.01–10 μM. The Hal/ZrO 2 /CB/GCE sensor possessed a pretty decent practicality with satisfactory RSD and recovery results for the determination of MP in peach, pear, and apple juices. Therefore, the Hal/ZrO 2 /CB/GCE sensor has important implication on the quite sensitive detection of MP.
研究领域:
分析化学
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纳米科学与技术
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环境监测
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食品安全
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电化学传感
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农药残留检测
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
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2015
·
IF 6.217
Jian Zhi,Houlei Cui,Angran Chen,Yian Xie,Fuqiang Huang
Dye-sensitized solar cells (DSSCs) on flexible plastic substrates usually suffer from a slower electron diffusion rate and insufficient surface area due to no sintering process . Therefore, the conversion efficiency (ƞ) of such flexible DSSCs is normally below 6%. Here, the highly flexible DSSCs with enhanced performance are fabricated at room temperature, employing 3D graphene decorated nanocrystalline TiO 2 films (3DGT) as anode on plastic substrates. Owing to the enhanced charge transportation and increased surface area from 3D conductive graphene skeleton, the 13 μm-thick 3DGT-0.85 (0.85 wt% 3D graphene plus TiO 2 nanoparticles) anode achieves a power conversion efficiency of 6.41%, which is 56% higher than pristine TiO 2 based anode. This efficiency is among the highest values for the previously reported TiO 2 photoanodes on plastic substrates.
研究领域:
材料科学
·
纳米科技
·
能源化学
·
光电转换
·
柔性电子学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2024
·
IF 5.8
Yuxing Sun,Lei Zhao,Juan Yang,Xiang Wang,Huanjun Peng,Jingdong Peng
Light absorption range, recycling stability and charge transfer efficiency are key to the performance of photocatalytic material. Based on these targets, a Al doped TiO 2 catalyst was synthesized by the evaporation-induced process, after processed by NaBH 4 reduction, the black TiO 2 doped with Al was finally prepared. Uv-vis DRS, EPR and XPS analyses confirm the expanded light absorption window (300 nm - 1000 nm) and the introduction of abundant oxygen vacancy after the reduction process. The final product BTiO 2 /Al-0.5 has a degradation rate of about 84 % over the tetracycline hydrochloride within 60 minutes, the reaction rate constant (k) is 10.6 times higher than the unreduced sample. The dramatic change of photocatalytic ability can be assigned to the broadened visible light absorption , increased charge separation efficiency, narrowed band gap and defect-enriched oxygen vacancy . This work offers insights into the fabrication of TiO 2 catalyst and the introduction of oxygen defect.
研究领域:
材料科学
·
光催化
·
环境功能材料
·
纳米材料
·
表面化学
·
半导体催化
✓ 已验证
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2018
·
IF 2.732
Qinghua Yang,Benxue Jiang,Shuilin Chen,Yiguang Jiang,Pande Zhang,Jun Wang,Shiqing Xu,Long Zhang
Al 2 O 3 : Er 3+ /Yb 3+ transparent ceramics codoped with Zn 2+ ions with intense upconversion and near infrared emission were prepared by conventional solid-state reaction and vacuum and hot isostatic pressing sintering. The effects of Zn 2+ incorporation to the structure, transparent, upconversion and NIR luminescence were discussed in detail. The as prepared Al 2 O 3 ceramics exhibited a total transmittance of ~ 75% in infrared regions (800–3300 nm) and ~ 50% in visible regions (500–800 nm). Under the excitation of a 980 nm laser diode , the as prepared Al 2 O 3 ceramics displayed two tense upconversion emission peaks of a green one centered at 550 nm and a red one centered at 660 nm and a tense near infrared emission peak centered at 1.532 µm, characteristic of Er 3+ emission. Compared with Er 3+ /Yb 3+ doped only, Zn 2+ codoped Al 2 O 3 :Er 3+ /Yb 3+ transparent ceramics showed higher upconversion and near infrared emission of ~ 11 times and ~ 4 times, respectively. The enhancement mechanism due to incorporation of Zn 2+ ions was also discussed in detail.
研究领域:
材料科学
·
光学材料
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无机非金属材料
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发光材料
·
陶瓷工程
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2021
·
IF 8.128
Xin-yu Hu,Mao-xiang Jing,Hua Yang,Quan-yao Liu,Fei Chen,Wei-yong Yuan,Le Kang,Dong-hong Li,Xiang-qian Shen
Poor room-temperature ionic conductivity and lithium dendrite formation are the main issues of solid electrolytes. In this work, rod-shaped alumina incorporation and graphite coating were simultaneously applied to poly (propylene carbonate) (PPC)-based polymer solid electrolytes (Wang et al., 2018). The obtained alumina modified solid electrolyte membrane (Al-SE) achieves a high ionic conductivity of 3.48 × 10 −4 S/cm at room temperature with a wide electrochemical window of 4.6 V. The assembled NCM622/Al-SE/Li solid-state battery exhibits initial discharge capacities of 198.2 mAh/g and 177.5 mAh/g at the current density of 0.1 C and 0.5 C, with the remaining capacities of 165.8 mAh/g and 161.3 mAh/g after 100 cycles respectively. The rod-shaped structure of Al 2 O 3 provides fast transport channels for lithium ions and its Lewis acidity promotes the dissociation of lithium salts and release of free lithium ions. The lithiophilic Al 2 O 3 and Graphite form intimate contact with metallic Li and create fast Li + conductive layers of Li-Al-O layer and LiC 6 layer, thus facilitating the uniform deposition of Li and inhibiting Li dendrite formation during long-term cycling. This kind of composite Al-SE is expected to provide a promising alternative for practical application in solid electrolytes.
研究领域:
材料科学
·
电化学
·
能源存储
·
固态离子学
·
纳米复合材料
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锂金属电池
✓ 已验证
DOI
高影响因子
Science China-Materials
·
2023
·Vol. 66
·期 5
·1810-1819
·
IF 8.1
Xiao Hongbin,Qian Qingkai,Zang Zhigang
Recently, all-inorganic cesium lead halide (CsPbX 3 (X = Cl, Br, and I) perovskite nanocrystals (NCs) have been extensively investigated for photocatalytic carbon dioxide (CO 2 ) reduction reaction (CO 2 RR). However, because the pristine CsPbX 3 NCs suffer from severe radiative recombination, it is imperative to elaborately design heterostructures to separate electron-hole pairs for achieving efficient CO 2 RR. Herein, palladium (Pd) nanoparticles (NPs) are anchored on CsPbBr 3 NCs by a photo-assisted approach for the first time. The as-prepared CsPbBr 3 @Pd NCs not only build Schottky junctions at the CsPbBr 3 /Pd interfaces that promote the carrier separation and suppress the radiative recombination, but also exhibit lower energy barriers for photocatalytic CO 2 RR than pristine CsPbBr 3 NCs according to the density functional theory calculations. The electron consumption rate reaches a striking peak of 46.2 µmol g −1 h −1 by using CsPbBr 3 @Pd NCs as photocatalysts for CO 2 RR, which is 4.8-fold of the counterpart of pristine CsPbBr 3 NCs. This work not only presents a photo-assisted strategy for anchoring Pd NPs on CsPbBr 3 NCs, but also demonstrates the great potential of using CsPbBr 3 @Pd NCs for photocatalytic CO 2 RR.
研究领域:
材料化学
·
光催化
·
纳米材料
·
环境化学
·
能源化学
·
半导体物理
·
催化化学
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2019
·
IF 4.561
Xiao-Qian Wei,Wan-Ju Zhang,Lu Lai,Ping Mei,Li-Mei Wu,Yan-Qun Wang
The effects of cationic surfactants on the properties of Pickering emulsions stabilized by silica nanoparticles (nano-SiO 2 ) were investigated. The zeta potential , three-phase contact angle ( θ ), and dynamic interfacial tension (DIT) were measured to analyze the interaction between hydrophilic nano-SiO 2 and four different cationic surfactants (i.e., dodecyltrimethylammonium bromide [DTAB], bis-quaternary ammonium salts [BQAS-12], multiple quaternary ammonium salts [MQAS-12], and dimethyldioctadecylammonium bromide [DDAB-18]). All these surfactants can naturally improve the stability of Pickering emulsions induced by hydrophilic nano-SiO 2 . The nano-SiO 2 /MQAS-12 mixtures exhibited the best ability to stabilize the O/W emulsions, followed by nano-SiO 2 /BQAS-12 mixtures. The nano-SiO 2 /DDAB-18 mixtures can induce emulsion inversion from O/W to W/O. All emulsions exhibited excellent salt tolerance and acid-base resistance properties. Determining the zeta potential showed that nano-SiO 2 had the highest negative charge at the pH of 9.5. Thus, the surfactant molecules can be adsorbed remarkably on the nano-SiO 2 surface. Modification with different cationic surfactants can significantly increase the θ value of nano-SiO 2 , but the bilayers for DTAB-12, BQAS-12, and MQAS-12, except for DDAB-18, were adsorbed. DIT curves indicated that competitive adsorption of the surfactants occurred between the oil/water interface and nano-SiO 2 surface. The competitive adsorption of MQAS-12 was stronger than those of BQAS-12 and DTAB-12. The nano-SiO 2 /DDAB-18 mixture had an apparent induction region and required a considerable amount of time to reach equilibrium. The modified nano-SiO 2 was also not adsorbed in the oil/water interface spontaneously, which may be due to the large size of particles compared with small surfactant molecules.
研究领域:
胶体与界面化学
·
纳米材料科学
·
乳液工程
·
物理化学
·
表面科学
✓ 已验证
DOI
高影响因子