Journal of Nanostructure in Chemistry
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2021
·Vol. 12
·期 6
·1075-1087
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IF 6.391
Wang Junlei,Wang Kuan,He Zhen-Hong,Li Song-Song,Zhang Rong-Rong,Guo Pengfei,Wang Weitao,Yang Yang,Liu Zhao-Tie
A solvothermal route was developed to synthesize hierarchical TiO 2 nanoflowers with tunable morphology, macroporous and mesoporous structure, and larger surface areas by varying the ratio of N , N -dimethylformamide to isopropyl alcohol without using surfactant and template. Morphology and microstructure, textural, crystalline, optical and photoelectric properties were characterized to investigate thoroughly the correlation of features and photoactivity of catalysts. The photoactivity was evaluated for the degradation of phenol through analyzing the phenolic compounds. The catalysts exhibited significantly high photocatalytic activity with the degradation rate of phenol of 95%, and the decrease of total organic carbon (TOC) was 82 ± 3% under ultraviolet radiation (UV) for 180 min at room temperature. Meanwhile, the excellent cyclic stability and regenerability were obtained during five cycles and continued illumination. The enhanced photocatalytic activity probably was attributed to larger surface areas, hierarchical porous structure, effective generation and separation of the charge carriers, and outstanding light-harvesting ability.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2013
·
IF 3.777
Xiao Peng,Yaqing Feng,Shuxian Meng,Bao Zhang
The TiO 2 photoelectrode containing pores of different sizes was fabricated by adding various amounts of polystyrene microspheres (188 nm) into the TiO2 paste, which was used as template agent during the sintering process. On the one hand, it was found that the photoelectrode with appropriate size of pores was beneficial for the enhancement of photovoltaic performance of the corresponding dye-sensitized solar cells (DSSCs) via efficient utilization of incident light. On the other hand, the presence of large pores would also tend to reduce the amount of dye-uptake resulting in the decrease of cell performance. Furthermore, a multi-layered stacking architecture of TiO 2 nanoporous film with pore size gradually increased from bottom FTO glass to the top of the film was developed and used as photoelectrode in DSSCs with N719 as the sensitizer. The photoelectric conversion efficiency of 7.80% was realized which is 17.6% higher than that obtained for DSSCs containing TiO 2 nanoporous films with uniform size of pores. UV–vis spectra measurement and electrochemical impedance spectroscopy analysis were carried out for further studying the effect of the pore size and the stacking pattern on the photoelctronic and electrochemical properties of the resultant DSSCs.
研究领域:
材料科学
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光伏技术
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纳米材料
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能源材料
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电化学
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2022
·
IF 9.965
Yuzhen Jiao,Yajie Chen,Wei Han,Shumei Liang,Wei Li,Guohui Tian
Metal-organic frameworks-based hybrids with desirable components, structures, and properties have been proven to be promising functional materials for photocatalysis and energy conversion applications. Herein, we proposed and prepared ZnSe sensitized hierarchical TiO 2 nanosheets encapsulated MIL-125(Ti) hollow nanodisks with sandwich-like structure (MIL-125(Ti)@TiO 2 \ZnSe HNDs) through a successive solvothermal and selenylation reaction route using the as-prepared MIL-125(Ti) nanodisks as precursor. In the ternary MIL-125(Ti)@TiO 2 \ZnSe HNDs hybrid, TiO 2 nanosheets were transformed from MIL-125(Ti) and in situ grown on both sides of the MIL-125(Ti) shell, forming sandwich-like hollow nanodisks, and the ratio of MIL-125(Ti)/TiO 2 can be tuned by changing the solvothermal time. The ternary hybrids possess the advantages of enhanced incident light utilization and abundant accessible active sites originating from bimodal pore-size distribution and hollow sandwich-like heterostructure, which can effectively promote CO 2 photoreduction reaction. Especially, the formed multi-channel charge transfer routes in the ternary heterojunctions contribute to the charge transfer/separation and extend the lifespan of charge-separated state, thus boosting CO 2 photoreduction performance. The CO (513.1 μmol g −1 h −1 ) and CH 4 (45.1 μmol g −1 h −1 ) evolution rates over the optimized ternary hybrid were greatly enhanced compared with the single-component and binary hybrid photocatalysts.
研究领域:
材料科学
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环境科学
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能源科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF POWER SOURCES
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2016
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IF 6.333
Ya-Ping Que,Jian Weng,Lin-Hua Hu,Ji-Huai Wu,Song-Yuan Dai
The morphology, microstructure and crystallography of titanium dioxide (TiO 2 ) have great effect on the photoelectric performance of dye-sensitized solar cells (DSSCs). Herein, flower-like 3D TiO 2 microstructures based on well-defined high-crystalline nanosheets are synthesized through a facile hydrothermal method . Especially, morphological evolution process and mechanism of this hierarchical structure are investigated. Due to the highly crystalline nature and smaller surface area of these nanosheets , the corresponding device shows an extremely high open-current voltage up to 0.84 V, which results from the less electron recombination. When applied as a scattering layer on top of the nanoparticle layer, the power conversion efficiency (PCE) can be significantly improved and give birth to a PCE value of 9.6%, which is 24.6% higher than that of an analogous device using nanoparticles (NP) (7.7%). As reflected by diffusion reflection spectra, intensity of the modulated photocurrent/photovoltage spectroscopy (IMPS/IMVS) and electrochemical impedance spectra (EIS), this hierarchical structure can not only enhance light harvesting, but also reduce electron recombination, facilitate electron transport and improve electron collection efficiency.
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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光伏技术
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半导体物理
✓ 已验证
DOI
高影响因子
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
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2020
·
IF 3.442
Song Chen,Juan Du,Lulu Shen,Weiyi Chen
Hierarchical materials are of great interest toward the development of catalysts because of their unique structures and large specific surface area. In this study, Ag-decorated TiO 2 (TiO 2 @Ag) nanowire nanofibers (NW NFs) were synthesized via the in situ decoration of Ag nanoparticles (NPs) on hierarchical TiO 2 NW NFs and their microstructure and catalytic activity for the removal of 4-nitrophenol were evaluated. TiO 2 NW NFs were first synthesized via the hydrothermal reaction of the electrospun TiO 2 NFs in a concentrated NaOH solution and then hydrothermally treated in a AgNO 3 solution to form the TiO 2 @Ag NW NFs. SEM observations showed that the TiO 2 @Ag NW NFs were assembled from numerous TiO 2 NWs subunits and exhibited a hierarchical and fibrous morphology with diameters in the range of 1–2 μm and lengths of tens of micrometers. TEM observations showed that many Ag NPs with diameters in the range of 4–10 nm were well grown on each TiO 2 NW with diameters of 20–40 nm. It was found that the TiO 2 @Ag NW NFs showed catalytic activity for the removal of 4-nitrophenol (4-NP), a representative contaminant. The catalytic removal efficiency of 4-NP by the TiO 2 @Ag NW NFs in the presence of visible light irradiation (0.639 min −1 ) was 3.2-fold higher than that in the absence of light irradiation (0.199 min −1 ), indicating that the TiO 2 @Ag NW NFs exhibit visible light-enhanced catalytic activity.
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Haitao Li,Qiang Gao,Guanshuai Wang,Bo Han,Kaisheng Xia,Chenggang Zhou
Catalytic performance of a heterogeneous cobalt-based catalyst for advanced oxidative process (AOP) correlates tightly with its structure and composition. The main objective of this study is to maximize the utilization and accessibility of cobalt sites while enhancing their activity and stability through rational structural and composition designs, and thus to achieve an excellent performance for heterogeneous peroxymonosulfate (PMS) activation. To this end, a novel CoTiO 3 /TiO 2 composite (CTT), composed of CoTiO 3 overlayer on nanosheets-assembled hierarchical TiO 2 nanospheres, was elaborately designed and synthesized. The resulting CTT possessed certain features including CoTiO 3 -rich surface, large surface area (114.8 m 2 g −1 ), and highly open porous channels, which afforded sufficient accessible active sites against undesirable particle agglomeration and shedding. Moreover, cobalt sites of CTT exhibited a higher activity toward PMS than those of Co 3 O 4 due to the composition-induced distinct adsorption nature, easy electron transfer, and strong bond-weakening ability. Benefitting from the unique combination of structural and compositional advantages, CTT manifested remarkable catalytic efficiency, low cobalt leaching (0.078 mg L −1 ), and excellent reusability in activation of PMS for degradation of the emerging antibiotic pollutant metronidazole (MNZ). The potential degradation pathway for MNZ and the catalytic mechanism were further elucidated. The design strategy proposed in this study may provide a new opportunity for future development of high-performance heterogeneous cobalt-based catalysts in remediation of aquatic environment.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2016
·Vol. 8
·期 21
·10928-10937
·
IF 7.76
Hai-Bo Huang,Yue Yang,Li-Hua Chen,Yun Wang,Shao-Zhuan Huang,Jia-Wei Tao,Xiao-Ting Ma,Tawfique Hasan,Yu Li,Yan Xu,Bao-Lian Su
Engineering hierarchical structures of electrode materials is a powerful strategy for optimizing the electrochemical performance of an anode material for lithium-ion batteries (LIBs). Herein, we report the fabrication of hierarchical TiO2/C nanocomposite monoliths by mediated mineralization and carbonization using bacterial cellulose (BC) as a scaffolding template as well as a carbon source. TiO2/C has a robust scaffolding architecture, a mesopore–macropore network and TiO2–C heterostructure. TiO2/C-500, obtained by calcination at 500 °C in nitrogen, contains an anatase TiO2–C heterostructure with a specific surface area of 66.5 m2 g−1. When evaluated as an anode material at 0.5 C, TiO2/C-500 exhibits a high and reversible lithium storage capacity of 188 mA h g−1, an excellent initial capacity of 283 mA h g−1, a long cycle life with a 94% coulombic efficiency preserved after 200 cycles, and a very low charge transfer resistance. The superior electrochemical performance of TiO2/C-500 is attributed to the synergistic effect of high electrical conductivity, anatase TiO2–C heterostructure, mesopore–macropore network and robust scaffolding architecture. The current material strategy affords a general approach for the design of complex inorganic nanocomposites with structural stability, and tunable and interconnected hierarchical porosity that may lead to the next generation of electrochemical supercapacitors with high energy efficiency and superior power density.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
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