CRYSTENGCOMM
·
2011
·Vol. 13
·期 11
·3905-3909
·
IF 4.006
Dongfei Sun,Xingbin Yan,Jiangtao Chen,Shengxue Yu,Litian Hu,Qunji Xue
In this paper, Zn2TiO4 and TiN nanofibers were prepared by a facile combination of electrospinning followed by thermolysis under different atmospheres. An N,N-dimethyl formamide (DMF)–ethanol solution of poly(vinylpyrrolidone) (PVP), Ti(IV)–isopropoxide (Ti(OC4H9)4) and zinc acetate (ZnAc) was used as the electrospinning precursor and the electrospun nanofibers were calcined at 600 °C in air to generate Zn2TiO4 nanofibers. Subsequently, a conversion from Zn2TiO4 nanofibers to TiN nanofibers was realized through a heat treatment at 1000 °C under an ammonia atmosphere. Investigations using field-emission scanning electron and transmission electron microscopes (FESEM and TEM) revealed the nano-scale fibrous morphology of the obtained products. Energy-dispersive spectroscopy (EDS) and X-ray diffraction (XRD) studies confirmed the chemical composition and crystalline structure of the Zn2TiO4 and TiN nanofibers, respectively. The electrochemical properties of the as-prepared TiN nanofibers indicated that the capacitance characteristic of the TiN phase was the electric double-layer capacitance. The value of the specific capacitance gradually decreased with the increase of discharge current density.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
LUMINESCENCE
·
2024
·Vol. 39
·期 4
·e4730
·
IF 3.2
Kang Cheng,Weichao Huang,Xinyong Gong,Chaoyong Deng
Near-infrared light sources have potential applications in many fields. Cr 3+ is a good luminescence centre to prepare near-infrared phosphors. Improving the performance of existing near-infrared luminescent materials has indeed attracted great interest from researchers. The luminescence properties of Zn 2 TiO 4 :Cr 3+ were improved by crystal field engineering strategies. Zn 2+ –Ti 4+ was partially replaced using a Li + –Nb 5+ ion pair based on the Zn 2 TiO 4 :Cr 3+ phosphors. Luminescence Cr 3+ -activated luminescent materials are sensitive to changes in the local crystal structure and crystal field environment. Doping of Li + –Nb 5+ increased the luminescence intensity up to 2.7 times that of the undoped sample. Also, the thermal stability of the phosphor was greatly increased by the replacement of Li + –Nb 5+ .
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Yajie Wang,Ziyi Zhang,Jie Li,Ying Tang,Liang Fang
Excellent spinel microwave dielectric ceramics (1- x )Zn 2 TiO 4 - x Li 2 MgTi 3 O 8 (ZTLMT x , x = 1/3 and 2/3) were prepared at relatively low densification temperatures of 1100 °C and 1080 °C, respectively. A disordered cubic phase with space group Fd -3 m was formed at x = 1/3, whereas an ordered cubic phase with space group P 4 3 32 was formed at x = 2/3. The ceramics at x = 1/3 and 2/3 exhibited promising microwave dielectric properties of ɛ r = 18.27 and 22.96, Q × f = 91,877 GHz and 75,186 GHz, and τ f = −42.3 ppm/°C and −21.05 ppm/°C, respectively. The large deviation between the experimental ԑ r and theoretical ε th of 1/3 and 2/3 ceramics were 18.3 % and 57 %, respectively, due to the underestimation of the ionic polarizability of Ti 4+ . The difference in their ɛ r , Q × f , and τ f were discussed by the structure, FWHM of A 1g , lattice energy and bond energy in detail.
研究领域:
材料科学
·
陶瓷学
·
物理学
✓ 已验证
DOI
高影响因子
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
·
2023
·
IF 4.1
Kang Cheng,Xinyue Liu,Weichao Huang,Xinyong Gong,Chaoyong Deng
Cr 3+ is an ideal activator for near-infrared phosphor. Cr 3+ ions have an electronic structure in which the outermost shell is not fully filled, which makes the emission of Cr 3+ susceptible to the crystal field environment and the change of local structural. Therefore, when Zn 2+ -Ti 4+ ion pairs are replaced with Al 3+ -Al 3+ /Ga 3+ -Ga 3+ ion pairs , changes in the crystal structure and the crystal field are strengthened, which improves the luminescence performances of Zn 2 TiO 4 :Cr 3+ phosphors. The thermal stability and the intensity of the luminescence can be clearly seen to have increased.
研究领域:
材料科学
·
无机化学
·
发光材料
·
固体物理
·
功能材料
✓ 已验证
DOI
高影响因子
ChemCatChem
·
2016
·Vol. 8
·期 13
·2289-2295
·
IF 4.724
Xiaoqin Sun,Shuwei Wang,Cai Shen,Xiaoxiang Xu
Introducing foreign elements is an appealing means to endow wide band gap semiconductors with visible-light responses. Here, we investigated a series of Rh-doped Zn 2 TiO 4 as water reduction photocatalysts. Our results show that Rh doping is effective to improve the visible-light response as well as surface hydrophilicity of Zn 2 TiO 4 . Efficient photocatalytic hydrogen evolution was observed after Rh doping and was found to be compositional dependent. The best performance was recorded for sample Zn 2 Ti 0.96 Rh 0.04 O 4 , with an apparent quantum efficiency of ≈0.74 % under full-range irradiation ( λ ≥250 nm) and ≈0.25 % under visible-light irradiation ( λ ≥420 nm). The light absorption and surface hydrophilicity are likely the controlling factors for the better activity. Theoretical calculations suggest that Rh doping is responsible for a band gap reduction and is due to a newly formed valence band composed mainly of Rh 4d orbitals at the top of the original valence band. The visible-light activity can be attributed to the electron excitations from this new valence band to the conduction band. Graphical Doped semiconductor : Rh doping is an efficient approach to endow wide band gap semiconductor Zn 2 TiO 4 with visible-light responses. Photocatalytic hydrogen production from water was greatly improved after Rh doping both under full-range and visible-light illumination. DFT calculations reveal the critical role of Rh in forming a new valence band. The high photocatalytic activity after doping can be understood as a result of more light absorption as well as improved surface hydrophilicity.
研究领域:
材料科学
·
光催化
·
氢能
·
半导体物理
·
计算材料科学
✓ 已验证
DOI
高影响因子
ChemistrySelect
·
2025
·Vol. 10
·期 37
·e03497
·
IF 2
Zilin Yang,Shuting Wang,Hongbo Jiang,Weixing Zhao,Meijuan Tian,Jingman Pang
A novel BaTiO 3 /Zn 2 TiO 4 /ZnO heterojunction composite was successfully synthesized via the molten salt method, and its piezoelectric catalytic performance for pollution degradation was evaluated with methyl orange (MO) as the target pollutant. After calcination at 900 °C for 3 h, the optimal sample demonstrated exceptional catalytic activity, with a MO degradation rate of up to 98.78%. Notably, even after four consecutive cycles, this catalyst maintained a degradation efficiency exceeding 85%, indicating favorable stability and reusability. Radical trapping experiments were carried out to explore the degradation mechanism, showing that silver nitrate (AgNO 3 ) significantly enhanced the degradation efficiency over time, while disodium ethylenediaminetetraacetate (EDTA-2Na), methanol (CH 3 OH), and tert-butyl alcohol (TBA) inhibited the reaction to varying degrees. The superior catalytic activity of the BaTiO 3 /Zn 2 TiO 4 /ZnO system is mainly attributed to the strong synergistic effect between its piezoelectric catalytic performance and peroxymonosulfate (PMS). During the piezoelectric activation of PMS for MO degradation, hydroxyl radicals (·OH), sulfate radicals (SO 4 −·), and superoxide anions (O 2 −·) serve as the main reactive oxygen species, playing a dominant role in the reaction. These findings further elucidate the piezoelectric catalytic mechanism of the BaTiO 3 /Zn 2 TiO 4 /ZnO system in MO degradation. Graphical The BaTiO 3 /Zn 2 TiO 4 /ZnO catalyst, under ultrasonic irradiation, synergistically activates peroxymonosulfate (PMS) and ambient oxygen. This process yields a suite of reactive species, including sulfate (SO 4 · − ) and hydroxyl (·OH) radicals, as well as superoxide anion radicals (·O 2 − ), which collectively degrade methyl orange (MO), resulting in the complete mineralization to CO 2 and H 2 O.
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）