CHEMISTRY-A EUROPEAN JOURNAL
·
2020
·Vol. 26
·期 30
·6894-6898
·
IF 4.857
Shuyu Zhou,Congping Li,Hao Fu,Jing Cao,Jian Zhang,Lei Zhang
Graphical Outstanding resemblance ! The first molecular model of perovskite PbTiO 3 has been successfully prepared by bottom-up assembly of lead-doped titanium-oxo clusters in the presence of p - tert -butylthiacalix[4]arene as stabilizing ligands. Structural characterization confirmed that the clusters have almost the same structure as that in PbTiO 3 (see figure). The nanoclusters showed high solution stability and can be applied as electron-transport materials in perovskite solar cells to give satisfactory efficiencies and high device stability. In this work we have successfully prepared two lead-doped titanium-oxo clusters with core structures that resemble isolated perovskite PbTiO 3 species. In the obtained highly symmetric Pb 8 Ti 7 -oxo cluster, the central TiO 6 octahedra are orthogonally extended to adjacent octahedra through corner-sharing and the eight dopant lead ions form a cubic arrangement, making it the first molecular model of perovskite PbTiO 3 . Moreover, the clusters readily dissolved in chloroform and showed high solution stability, as confirmed by MALDI-TOF MS measurements. Based on such solution processability, they can be easily spin-coated to form homogeneous films, which were employed as electron-transport materials in perovskite solar cells to give an average power conversion efficiency of around 15 % and improved device stability. This newly developed bottom-up cluster assembly method provides an efficient approach to the construction of atomically precise models of perovskite metal oxides as well as potential molecular tools to extend their applications.
研究领域:
材料化学
·
能源科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2020
·
IF 5.774
Yutang Kang,Shihui Jiao,Yue Zhao,Boran Wang,Zhenwei Zhang,Wen Yin,Yumei Tan,Guangsheng Pang
Both high permeability and high selectivity are advantageous for separation membrane materials. It is a huge challenge to fabricate a membrane that simultaneously possesses both high permeability and high rejection. Here, we fabricated a TiO 2 nanofibers ultrafiltration membrane by depositing hydrogen titanate nanofibers on a porous titanium substrate and sintering at 450 °C. The porous titanium supported TiO 2 nanofibers ultrafiltration membrane has a superhydrophilic separation layer and a high pure water flux of 940 L m −2 h −1 bar −1 . The average pore size of the TiO 2 nanofibers ultrafiltration membrane is 14 nm. The nanoparticles that particle size is smaller than pore size of TiO 2 nanofibers ultrafiltration membrane such as Bovine serum albumin (BSA, 11 nm) and 3 nm TiO 2 nanoparticles can be rejected with high permeation flux and high rejection efficiency. The obtained ultrafiltration membrane exhibits excellent antifouling property, the flux recovery ratio reaches to 97%. Also, the fouling of the TiO 2 nanofibers ultrafiltration membrane can be removed by heating treatment, the permeation flux of the membrane can be easily recovered.
研究领域:
材料科学
·
环境工程
·
膜技术
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2023
·
IF 7.7
Haofei Ma,Ziqi Wang,Peng Yuan,Boxiong Shen,Jie Xu
Since the yield of titanium-bearing blast furnace slag (TF) during the smelting of vanadium titanium magnetite is large, it is urgent to find ways to recycle it and implement its value-added utilization. In this study, a perovskite-rich photocatalyst was prepared by acid-washing of TF, and then Ce was doped to modify it for photocatalytic removal of gaseous toluene under the irradiation of visible light. XRD, XRF and XPS analyses demonstrated that the perovskite phase was enriched after the acid-washing, and the content of CaTiO 3 in the acid-washed slag (AS) also increased after Ce doping. The combined N 2 adsorption-desorption, UV Vis DRS, EIS, PL , and ESR analysis results indicated that the photocatalytic performance of the mentioned photocatalyst was related to the Ce dopant content. The AS doped with 20% Ce (20% Ce-AS) had a lower band gap and larger specific surface area than the others catalysts. Under visible light radiation , more active radicals were produced, and the removal efficiency of toluene reached 92.08% for 20% Ce-AS. In addition, the results of the in situ DRIFTS tests indicated that toluene was gradually degraded by the Ce-doped perovskite-type photocatalyst to alcohols and aldehydes and mineralized to H 2 O and CO 2 . This study is expected to provide a new approach for the technical development of the value-added utilization of TF coupled with the efficient removal of toluene.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
·
2023
·Vol. 148
·期 22
·12739-12750
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IF 4.4
Liang Kaili,Liu Yang,Hu Lishuang,Liang Jiashun,Lv Tiancheng,Wu Wei,Wang Yanping,Tu Zhiqiong,Hu Shuangqi
Micron-sized titanium particles have potential applications as energetic metal high-enthalpy fuel materials. The molecular perovskite energetic material DAP-4 (H 2 dabco)[NH 4 (ClO 4 ) 3 ] is a potential high-energy oxidizer in solid rocket propellants. To explore the combustion mechanism and energy output of DAP-4-based Ti composites, the combustion characteristics of DAP-4/Ti and F/DAP-4/Ti were studied by electrode ignition device. The results show that the burning rate of DAP-4 can be adjusted by controlling the mass ratio of DAP-4/Ti. After adding Ti into DAP-4, the heat release, self-sustaining combustion time and flame front propagation velocity are greatly increased to 9,113 J g −1 , 265 ms and 0.225 mm ms −1 , respectively, better than those of DAP-4. With Ti added, the decomposition peak temperature of F/DAP-4/Ti dropped from 381.5 to 360.4 ℃. The experimental results contribute to a better understanding of the chemical reaction mechanism and energy release characteristics of DAP-4-based propellants containing Ti.
研究领域:
推进剂化学
·
燃烧与爆炸科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Liping Fang,Kai Wang,Chen Han,Xinyong Li,Pei Li,Jieshan Qiu,Shaomin Liu
Piezocatalysis utilizes mechanical energy to achieve the required charge separation for redox reactions, a promising method for clean H 2 O 2 production. However, the efficiency of conventional piezocatalysts is limited by the undesirable low piezoelectricity. Herein, novel piezocatalysts composed of La, Sr, Co (Fe) in simple single perovskites (La 0.5 Sr 0.5 FeO 3-δ and La 0.5 Sr 0.5 CoO 3-δ ) and Ruddlesden-Popper (R-P) type perovskites (LaSrFeO 4-δ and LaSrCoO 4-δ ) are developed for piezocatalytic H 2 O 2 production. Results indicate that Fe-containing catalysts outperform Co-containing counterparts and the unique R-P perovskite oxides demonstrate significantly enhanced piezocatalytic performance than the corresponding single perovskites. For example, via piezocatalysis, the LaSrFeO 4-δ exhibits H 2 O 2 yields of 548 (in 10 % ethanol) and 247 µmol g −1 h −1 (without sacrificial agent), improved by a factor of 1.14, 4.94, or 21.73 compared to La 0.5 Sr 0.5 FeO 3-δ , LaSrCoO 4-δ , or La 0.5 Sr 0.5 CoO 3-δ , respectively. The piezoelectricity is an overwhelming factor in determining the H 2 O 2 generation. Furthermore, the piezoelectricity and oxygen vacancy (OV) content is well correlated. The R-P phase with lower OV exhibits a higher piezoelectricity because of the eliminated pining effect to the polarization domain reversion. Mechanism exploration suggests that H 2 O 2 formation stems from the efficient O 2 reduction via a 2-electron transferring pathway, during which the piezoelectric polarization drives the charge separation and transportation, favoring the redox reactions.
研究领域:
材料科学
·
环境科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Research and Technology-JMR&T
·
2020
·
IF 5.289
Zhijun Wang,Baoqiang Xu,Jia Yang,Bin Yang,Heng Xiong,Guobo Yang,Fengkang Wang
A route is present for preparing porous titanium scaffolds with open and interconnected pore morphology through calcium thermal in-situ reduction of TiO precursor. Titanium and dioxide titanium powders, with ammonium carbonate as the space holder, were used to prepare porous precursor whose main phase is TiO by a sintering process. Then calcium vapor was conduced to reduce the precursor and CaO was removed by leaching to obtain porous titanium structures. The morphology, pore structure, phase analysis of porous titanium precursor and porous titanium scaffolds were investigated by means of XRD, SEM and EDS. The porosity was observed by Archimedes method. By this route, the porous titanium with multi-gradient pore sizes ranging from a few microns to several hundred microns was formed. The porous titanium is of multi-gradient pore size distribution of 100 μm bigger, 10 μm∼100 μm and 10 μm smaller. The micro-pores on the pore walls increases connectivity between the macro-pores throughout the porous titanium interior. The porous titanium obtained by this method has a porosity of 50–65% and a titanium content more than 99%.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF REFRACTORY METALS & HARD MATERIALS
·
2020
·
IF 3.407
Longqing Chen,Wenbin Qiu,Hao Deng,Xiaoliang Yang,Yangyipeng Song,Jun Zhu,Jun Tang
The shrinkages presented in sintering process of tungsten alloys are extremely detrimental to their practical applications in fusion reactors. Positively in this work, we effectively reduced the shrinkages via synergistically applying Ti-doping and annealing process on tungsten‑potassium (WK) alloys. This shrinkage-fill effect only works in the one with trace amount of titanium doping, such as 0.05 wt%Ti or 0.5 wt%Ti. Due to such effect, the compressive strength was improved by ~18%. Based on morphological and elementary analyses, we speculated that the Ti-rich particles along the grain boundaries of WK alloys were activated and migrated into shrinkages during annealing. Further Ti doping (e.g. 1wt.%Ti) led to nanoscale grain refinement in WK alloys, which almost doubled the compressive strength. In this case, an unconventional grain-refinement model was proposed. Furthermore, anomalous grain growth was observed in WK-3wt.%Ti, which was attributed to the formation of Ti-rich regions and the corresponding raise of energy in grain boundaries. The fabricating strategies in this work may benefit the design of refractory tungsten alloys with less shrinkages and ultra-fine grains.
研究领域:
材料科学
·
核能工程
✓ 已验证
产品关联
DOI
高影响因子
SOLAR ENERGY MATERIALS AND SOLAR CELLS
·
2017
·
IF 4.784
Xiaoyan Gan,Ou Wang,Keyong Liu,Xiangjun Du,Liling Guo,Hanxing Liu
We present the fabrication and characterization of two dimensional (2D) perovskites (PEA) 2 (MA) m-1 Pb m I 3 m+1 (PEA=phenylethylammonium, MA=methylammonium, m=1,2,3) for application as light absorbers in solar cells. Films of 2D perovskite series show high stability under humid air , with band gaps decreasing with increasing m values, from 2.36 eV for (PEA) 2 PbI 4 (m=1) to 1.94 eV for (PEA) 2 (MA) 2 Pb 3 I 10 (m=3). Owning to the smaller bandgap, favorable vertical growth characteristics, and appropriate energy band structure of (PEA) 2 (MA) 2 Pb 3 I 10 , planer perovskite solar cells based on (PEA) 2 (MA) 2 Pb 3 I 10 exhibit best cell performance. Incorporation of TiO 2 nanorod arrays into (PEA) 2 (MA) 2 Pb 3 I 7 based perovskite solar cells are further found to be useful in improving the cell performance, ascribing to the improved quality and coverage of the perovskite films, as well as the enhanced electronic contact between the perovskites and the electron transporting layer. By optimizing the TiO 2 NR lengths, an efficiency of 3.72% is obtained for (PEA) 2 (MA) 2 Pb 3 I 10 perovskite cells with 600 nm-long TiO 2 NRs as scaffolds, which is more than a time higher than that of the planer analogue device. Our study to design 2D perovskite solar cells demonstrates the importance of material structure and device configuration for efficient solar cells, highlighting the validity of TiO 2 nanorods in functionalizing 2D perovskites for photovoltaic applications.
研究领域:
材料科学
·
光伏技术
✓ 已验证
DOI
高影响因子
ACS Applied Energy Materials
·
2023
·
IF 6.4
Zihui Liang,Yang Shi,Tian Yuan,Bowen Jin,Yidong Ming,Fengxiang Chen,Shimin Wang,Jing Li,Congcong Wu
The synthetical strategy of methylamine (MA) molecular treatment for fabricating perovskite film has been attracting increasing attention because of the ease of fabrication feature and the high-throughput process. In this approach, we found both of perovskite salts (MAI and PbI2) and crystals have been used as the source materials for the interaction with MA molecules. Even though both alternatives are applicable, the reaction routes toward perovskite crystalline film are distinct, which correlates with the photovoltaic performance and the fabrication process design. Therefore, we systematically studied the difference between perovskite salts and crystals with respect to precursor solubility, crystallization dynamics, perovskite crystal structure, and photoelectric properties. The results show the configuration and the crystallization dynamic of the salts and crystal-derived solution are different. The salt-derived solution consists of iodoplumbate complexes, while the crystal-derived solution is composed of perovskite sheet intermediates. Because of the ordered stacking behavior of the perovskite sheet intermediates, the crystal-derived perovskite films showed faster crystallization and preferred crystal orientation, which results in superior charge carrier transport properties and higher conversion efficiency. The disclosure of the distinct features between salts and crystals provides guidelines to modulate the solution chemistry for higher photovoltaic performance.
研究领域:
材料科学
·
光伏技术
·
化学工程
✓ 已验证
DOI
高影响因子
Journal of Materials Research and Technology-JMR&T
·
2022
·
IF 6.267
Shushi Zhang,Zhenyang Wang,Peng Hu,Jiating Rao,Jianliang Zhang,Jing Pang
The HIsmelt process is well suited for smelting vanadium-titanium magnetite and has significant potential. In this paper, the vanadium and titanium distribution behavior at 1450 °C in the basicity range of 0.3–1.2 during HIsmelt smelting vanadium titano-magnetite was investigated experimentally for the first time. According to thermodynamic calculations combined with experimental validation, lower C content increases the activity coefficients of vanadium and titanium in the metal. Higher basicity decreases the activity coefficients of TiO 2 and SiO 2 in the slag, improves the distribution ratio of vanadium and titanium. Increasing C content and reducing basicity could increase the content of vanadium in the metal and TiO 2 in the slag, which is favorable to vanadium extraction and titanium recovery. Furthermore, the V and Ti content in the hot metal increased significantly with rising smelting temperature. Higher smelting temperatures promote vanadium distribution into hot metal but not titanium distribution into slag. Finally, The Si and Ti distribution ratios have a positive connection according to the fitted models.
研究领域:
冶金学
·
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
PHYSICA SCRIPTA
·
2023
·Vol. 99
·期 1
·015526
·
IF 2.9
Tao Zhang,Siyu Cai,Nina Liang,Yalei Gao,Yuanpeng Li,Fuchi Liu,Lizhen long,Jun Liu
Zero-dimensional (0D) and one-dimensional (1D) mixed heterostructure semiconductors can bring superior electrical and optoelectronic performances due to the synergistic advantages of different dimensionalities. Here, a metal-semiconductor–metal (MSM) ultraviolet (UV) photodetector based on 1D-0D TiO2/CsPbBr3 heterostructure semiconductor is constructed, which exhibits excellent photodetection performance. A back-to-back Schottky contact is formed in the MSM (Au/TiO2/Au) structure due to the large band-energy bending resulted from the abundant surface-states at 1D-TiO2 surface. Under an applied voltage, a small saturation current flows through the device. Benefiting from the decoration of CsPbBr3 QDs, the dark current of MSM photodetectors can be further suppressed, and producing the improved on/off ratio (Ilight/Idark), photoresponsivity (Rλ), and detectivity (D*). PL properties study suggested that an energy transfer is occurred between the 0D-CsPbBr3 and 1D-TiO2. The TiO2/CsPbBr3 heterojunctions are beneficial for photo-induced charge transfer in hetero-interface because of the type-II energy-band alignment, but not non-radiative energy transfer from 0D-CsPbBr3 to 1D-TiO2. On the whole, this study depicts a fascinating coupling architecture of mixed-dimensional materials toward implementing low-cost and high-performance optoelectronic devices.
研究领域:
材料科学
·
光电子学
✓ 已验证
DOI
高影响因子
Frontiers of Environmental Science & Engineering
·
2022
·Vol. 16
·期 8
·1-16
·
IF 6.048
Liu Xiaoman,Tian Chang,Zhao Yanxia,Xu Weiying,Dong Dehua,Shih Kaimin,Yan Tao,Song Wen
Application of ceramic membrane (CM) with outstanding characteristics, such as high flux and chemical-resistance, is inevitably restricted by membrane fouling. Coagulation was an economical and effective technology for membrane fouling control. This study investigated the filtration performance of ceramic membrane enhanced by the emerging titanium-based coagulant (polytitanium chloride, PTC). Particular attention was paid to the simulation of ceramic membrane fouling using four widely used mathematical models. Results show that filtration of the PTC-coagulated effluent using flat-sheet ceramic membrane achieved the removal of organic matter up to 78.0%. Permeate flux of ceramic membrane filtration reached 600 L/(m 2 · h), which was 10-fold higher than that observed with conventional polyaluminum chloride (PAC) case. For PTC, fouling of the ceramic membrane was attributed to the formation of cake layer, whereas for PAC, standard filtration/intermediate filtration (blocking of membrane pores) was also a key fouling mechanism. To sum up, cross-flow filtration with flat-sheet ceramic membranes could be significantly enhanced by titanium-based coagulation to produce both high-quality filtrate and high-permeation flux.
研究领域:
环境工程
·
水处理技术
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）