APPLIED CATALYSIS B-ENVIRONMENTAL
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2024
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IF 20.2
Rassu Pietro,Cappai Luca,Stagi Luigi,Liu Ruirui,Enzo Stefano,Mulas Gabriele,Garroni Sebastiano,Malfatti Luca,Innocenzi Plinio,Ma Xiaojie,Wang Bo
Alcohol and water photooxidation reactions are employed in concert with optical spectroscopy analyses to demonstrate the occurrence of multiple and distinctive charge-transfer (CT) mechanisms in the environmental photocatalyst MIL-125(Ti). The contribution of ligand-to-metal CT (LMCT) mechanisms increases at wavelengths lower than 320 nm while that of node oxygen-to-metal CT (OMCT) mechanisms increases at longer wavelengths. The localization of photogenerated holes on different atoms leads to a selective reactivity of the framework depending on the mechanism and, during hydroxylation processes, to its spontaneous transition to the isostructural MIL-125-OH(Ti) and the development of an additional LMCT mechanism with a long-lived emission. Furthermore, a previously unidentified and extrinsic CT mechanism is spectroscopically related to the formation of terephthalate-based oligomers . The coexistence of distinctive CT mechanisms in MIL-125(Ti) implies their critical role in catalyst efficiency, and mastering them proves to be a powerful and simple strategy to produce the valuable MIL-125-OH(Ti).
研究领域:
材料科学
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环境科学
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光化学
✓ 已验证
DOI
高影响因子
SURFACE & COATINGS TECHNOLOGY
·
2017
·
IF 2.589
Lianbo Wang,Ming Chen,Huabing Liu,Chuanhai Jiang,Vincent Ji,Florent Moreira
In present work, the ternary Ni-Ti-CeO 2 composite coatings were electrodeposited on Al matrix composite (CNT/7075) in traditional Watts' solution containing various concentrations of CeO 2 nanoparticles and constant concentration of Ti microparticles . The effects of CeO 2 nanoparticles on microstructure and corrosion resistance of the obtained composite coatings were comprehensively investigated. The incorporation of moderate CeO 2 nanoparticles (less than 10 g L − 1 in Watts' solution) gave rise to grain refinement, random-orientation growth of nickel deposit and smooth surface of the composite coating. Corrosion tests of the Ni-Ti-CeO 2 composite coatings in 3.5 wt% sodium chloride (NaCl) at 25 °C illustrated the optimised microstructure favoured the enhancement of corrosion resistance. Further analyses of the corrosion behavior demonstrated that the embedded CeO 2 nanoparticles facilitated the formation of a compact passive film on the surface of the composite coatings during corrosion and promoted the formation of TiO 2 on the surface of Ti microparticles. The formation of TiO 2 not only protected the Ti metal particles but also helped to improve the corrosion resistance of the composite coatings, because the TiO 2 coated Ti microparticles decreased the attack probability of nickel deposits by corrosive medium. Typically, the Ni-Ti-CeO 2 composite coating electrodeposited in Watts' solution containing 10 g L − 1 CeO 2 nanoparticles possessed the best corrosion resistance and excessive CeO 2 nanoparticles deteriorated the corrosion resistance.
研究领域:
材料科学
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电化学
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表面工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Xiumei Wu,Yunping Li,Xiangming Chen,Shu Yu
Ti doping SiTiOC ceramics were prepared by sol-gel method with tetrabutyl titanate (TBT) as modifier. The thermal stability of SiTiOC ceramics with various Ti contents was studied. Meanwhile, the influence of Ti addition on the pyrolysis behavior of SiTiOC xerogel and the structure evolution of SiTiOC ceramics were investigated. The ceramic yield of SiTiOC xerogels were improved greatly by introducing TBT, while the improvement of ceramic yield had an upper limit, for the simultaneous increase of volatile CH 3 O(CH 2 ) 3 OH. At 900 °C pyrolysis, SiTiOC ceramics were amorphous, and Ti existed by oxides. At 1200 °C and 1400 °C pyrolysis, the crystallinity of SiTiOC ceramics increased, TiC phase appeared in ceramics due to the carbothermal reduction of titanium oxides. With increased Ti contents, TiC contents increased in ceramics attributed to the preferentially carbothermal reduction of titanium oxides. The addition of Ti improved the thermal stability of SiOC ceramic system, but such an improvement was sensitive to the Ti contents. 0.05Ti-1400 ceramic exhibited the highest thermal stability with the mass change of 6.51 %. Because the oxide scale of 0.05Ti-1400 ceramic was complete and dense, with lowest thermal stress and oxygen diffusion rate for the least TiO 2 formed in the oxide scale. Concurrently, the TiO 2 particles formed with long rod-like which distributed uniformly in oxide scale that can toughen the oxide scale. While for 0.1Ti-1400 and 0.2Ti-1400 ceramics, the increase of Ti outward diffusion degree damaged the oxide scale and accelerated the oxidation of free carbon.
研究领域:
材料科学
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无机化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Wei Zhang,Wei Liu,Guoliang Li,Wei Du,Jianbo Lu,Jianguo Song,Qixia Yang,Xiangming Li,Huizhong Xu,Xu He,Jun Ma
The para arsanilic acid ( p -ASA) used as feed additive in the poultry and swine industries tends to transform into more toxic inorganic arsenic (As(V) and As(III)), leading to a greater risk to human health and environmental system. In this study, simultaneous adsorption and oxidation of p -ASA was achieved by a synthesized highly efficient nanostructured Fe-Ti-Mn composite oxide (FTMO), with a high specific surface area of 424.7 m 2 /g. The maximum adsorption capacity for p -ASA could be as high as 45.6 mg/g, meanwhile the combined oxidation/photo-oxidation processes led to the formation of intermediate containing hydrazine group, however, without release of toxic inorganic As(III) and As(V). The p -ASA adsorption by FTMO was verified as the chemisorption process with the formation of inner-sphere complexes at the solid/water interface, which was prominently influenced by solution pH, coexisting ions and humic acid, however relatively insensitive to ionic strength. The systematic characterization by FTIR, XPS, EPR and XANES revealed that Fe phase of FTMO played the dominant role for p -ASA adsorption, while Mn and Ti phases were responsible for the oxidation and photo-oxidation of p -ASA, respectively.
研究领域:
环境科学
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材料科学
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毒理学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Nano Materials
·
2023
·
IF 5.9
Songbo Wang,Yidan Wang,Jia Li,Shuang Guo,Chengzhen Meng,Lun Pan,Ji-Jun Zou,Yawei Shi,Lei Zhang,Zhen Yin,Na Tang
In order to address the current energy and environmental challenges, photoelectrochemical (PEC) water splitting has been widely studied, and the key point about the efficient PEC process is how to develop highly active photoanode catalysts. In this article, we report a two-step hydrothermal and electrodeposition approach to prepare a cobalt (oxy)hydroxide (CoOOH)-modified Ti-Fe2O3-In2O3 electrode by synergy of electron modulation and a heterojunction structure for promoting PEC water splitting. Under a bias of 1.23 V vs RHE, the optimized Ti-Fe2O3-In2O3/CoOOH photoanode demonstrated remarkable photocurrent density and hydrogen evolution rate as high as 1.33 mA cm–2 and 22.8 μmol cm–2 h–1, which was 5.11-fold and 5.14-fold that of bare α-Fe2O3, respectively. Characterization results indicate that Ti-doping will alter the electronic structure and improve the charge carrier density, whereas the construction of a heterojunction can realize the spatial separation of charge carriers. Meanwhile, the outer CoOOH ultrathin layer can provide a large amount of oxygen evolution reaction sites and promote the surface reaction. This work suggests that the PEC performance of Fe2O3-based photoanodes can be improved effectively by the synergy of electronic modulation and heterojunction construction.
研究领域:
能源与环境科学
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材料科学
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光化学
✓ 已验证
产品关联
DOI
高影响因子
Catalysis Science & Technology
·
2015
·Vol. 5
·期 4
·2260-2269
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IF 5.426
Qiulin Zhang,Xin Liu,Ping Ning,Zhongxian Song,Hao Li,Junjie Gu
Mesoporous Ce–Ti–MoOx catalysts have been prepared by stabilization with an in situ formed carbon template and used for selective catalytic reduction of NOx with NH3 (NH3-SCR). The Ce–Ti–MoOx catalysts were characterized by N2 adsorption–desorption, XRD, HR-TEM, H2-TPR and XPS analysis. It was found that the stabilization with a carbon template obviously improved the NOx conversion of the Ce–Ti–MoOx catalyst and the pore distribution. The Ce–Ti–MoOx catalyst stabilized with a carbon template at 850 °C in N2 exhibited the best NH3-SCR activity and showed a uniform mesopore distribution, and more than 90% NOx conversions were obtained at 175–425 °C with a GHSV of 60 000 h−1. The high stabilization temperature with a carbon template in N2 not only led to an increase in specific surface area, pore volume and low-temperature SCR activity, but also contributed to the enhanced redox properties, highly dispersed titanium or molybdenum species and narrow mesopore distribution. The treatment of Ce–Ti–MoOx with a high calcination temperature for removal of the carbon template led to a drastic decrease in surface area, an abrupt decrease in surface oxygen and cerium, production of rutile TiO2, and a correspondingly low SCR activity.
研究领域:
环境科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
NANOTECHNOLOGY
·
2022
·Vol. 33
·期 50
·505602
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IF 3.953
Fan Fang,Haochen Liu,Zuoliang Wen,Chenxi Liu,Bing Xu,Zhikuan Zhang,Kai Wang,Mehmet Ertugrul,Wei Lei,Xiao Wei Sun
Colloidal quantum dots (QDs) are promising luminescent materials for display and lighting, but their stability has long been an issue. Here, we designed a passivation strategy of doping Ti ions into the shell of alloyed CdZnSeS@ZnS QDs. The results showed that Ti ions were successfully doped into the ZnS shell and the stability of QDs was improved. In the aging test, the Ti ions doped QDs maintained 51.4% of the initial performance after 90 h of aging, while the pristine QDs decreased to less than 25% of the initial value. In addition, we discuss the reasons why Ti ions doping improves the stability of QDs. Ti ions are found to form Ti–S bonds in the ZnS shell, which has high binding energy and strong oxidation resistance. Most importantly, since there is no external physical insulating coating, the optimized QDs can also be directly used in electroluminescent devices, showing great potential in electroluminescence applications.
研究领域:
材料科学
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光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
·
2025
·
IF 7.2
Xianghan Cheng,Zhongmin Liu,Ruilin Wang,Yajun Guo,Wenyuan Han,Yong-Zheng Zhang,Da-Shuai Zhang,Xiuling Zhang,Suijun Liu,Longlong Geng
Regulating the separation and transport capabilities of the photocarriers is an important strategy to enhance corresponding activity of photocatalysts. In this work, novel Ti-MOF/Ti 3 C 2 heterojunction with face-to-face intimate contact was design and synthesized through a hydrothermal assemble route. The negatively charged Ti 3 C 2 not only facile the absorb of Ti nodes but also offer rich nucleation sites for the in-situ growth Ti-MOF. Under visible light irradiation, the optimized TM-0.05 exhibited exceptional photocatalytic activity and reusability during tetracycline photocatalytic degradation process. The rate constant reaches 1.83 × 10 −2 min −1 over TM-0.05, which was 5.3 times and 2.3 times higher than that of sole Ti-MOF and Ti 3 C 2 , respectively. Combined photoelectric characterization confirmed the improved photocatalytic activity was predominantly due to the excellent conductivity of Ti 3 C 2 and the tight interface connection between the two semiconductors, thus accelerating the interfacial charge separation and transport. Scavenger experiments, EPR, and LC-MS analysis confirmed the key role of •O 2 - , •OH and photogenerated holes during tetracycline degradation, and finally a possible mechanism was postulated. This work provides a new approach for constructing MOF/MXene structures via in situ self-assembly strategy, and expand their application in refractory pollutants photocatalytic degradation process.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Metals
·
2023
·Vol. 13
·期 2
·264
·
IF 2.9
Dongdong He,Hui Wang,Weidong Huang,Xinxi Chen,Guofu Lian,Yu Wang
In this study, TiB + La2O3/Ti-6Al-4V composites were successfully prepared by in situ reaction using selective laser melting technology. The effect of LaB6content on the fabrication quality, microstructure evolution and mechanical properties of the composite samples was investigated. The results show that the relative density of the sample gradually decreased from 98.56% to 96.57% as LaB6content increased from 0 wt% to 3 wt%. With increasing LaB6content, TiB precipitates gradually aggregated and grew from a discrete needle-like structure to a dendritic structure, before eventually developing a cell-like structure. The dislocations piled up around the TiB and La2O3reinforcements, which impeded the motion of the dislocations and led to the enhancement of the tensile strength of the samples. Different from the addition of a single reinforcement due to the combined strengthening effect of the micrometer-scale and nanoscale reinforcements, the strength of the samples was increased significantly. The Ti-6Al-4V sample with 3 wt% LaB6addition showed the most significant strengthening effect. Compared to the pure Ti-6Al-4V sample, the 3 wt% LaB6addition sample gained a 35.71% increase in hardness and a 14.5% increase in tensile strength. Additionally, wear volume was reduced by 47.5%. The results revealed that the addition of LaB6was a potential way to improve the mechanical performance of the titanium alloys in the additive manufacturing process.
研究领域:
材料科学
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机械工程
✓ 已验证
产品关联
DOI
高影响因子
Frontiers in Chemistry
·
2022
·
IF 5.545
Wang Chuan,Cao Zhifen,Huang Hongtao,Liu Hong,Wang Sha
Nitrate pollution is already a global problem, and the electrocatalytic reduction of nitrate is a promising technology for the remediation of wastewater and polluted water bodies. In this work, Co3O4/Ti electrodes were prepared by electrodeposition for the electrocatalytic reduction of nitrate. The morphology, chemical, and crystal structures of Co3O4/Ti and its catalytic activity were investigated. Then, the electrocatalytic nitrate reduction performance of Co3O4/Ti as the cathode was evaluated by monitoring the removal efficiencies of nitrate (NO3−-N) and total nitrogen (TN), generation of reduction products, current efficiency (CE), and energy consumption (EC) at different operating conditions. Under the catalysis of Co3O4/Ti, NO3− was reduced to N2 and NH4+, while no NO2− was produced. After the introduction of chloride ions and IrO2-RuO2/Ti as the anode, NH4+ was selectively oxidized to N2. The removal efficiencies of NO3−-N (at 100 mg/L) and TN after 2 h were 91.12% and 60.25%, respectively (pH 7.0; Cl− concentration, 2000 mg/L; current density, 15 mA/cm2). After 4 h of operation, NO3−-N and TN were completely removed. However, considering the EC and CE, a 2-h reaction was the most appropriate. The EC and CE were 0.10 kWh/g NO3−N and 40.3%, respectively, and electrocatalytic performance was maintained after 10 consecutive reduction cycles (2 h each). The cathode Co3O4/Ti, which is prepared by electrodeposition, can effectively remove NO3−-N, with low EC and high CE.
研究领域:
环境科学
·
电化学工程
·
废水处理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of the Australian Ceramic Society
·
2023
·Vol. 59
·期 5
·1231-1239
·
IF 1.9
Zhang Mengwen,Jiang Binyang,Yang Lutong,Cao Na,Li Zhaosheng,Fan Lei,Yang Shoulei
The emerging oscillatory pressure sintering technology is used to prepare high-performance Al 2 O 3 -Ti(C,N) ceramic tools for high-speed cutting. By recording the displacement during sintering, the sintering shrinkage rate of the Al 2 O 3 -Ti(C,N) composite was calculated, and the stress exponent n and sintering activation energy Q were calculated according to creep theory to determine the densification mechanism. In addition, the evolution of phases, microstructure and hardness of the composite was also observed. Results show that during oscillatory pressure sintering process at 1400 °C and 1300 °C, the stress exponent of Al 2 O 3 -Ti(C,N) composite is around 2.2 and the sintering activation energy is 486 kJ mol −1 , indicating that the densification mechanism is a diffusion-controlled grain boundary sliding of Al 2 O 3 phase. Additionally, as the oscillatory pressure increases, the average grain size of the Al 2 O 3 decreases and the Vickers hardness increases. Hardness achieves the highest 22.7 GPa when the median oscillatory pressure is 70 MPa at 1400 °C, which is 1 GPa higher than that of static pressure of 70 MPa.
研究领域:
材料科学
·
机械工程
✓ 已验证
产品关联
DOI
高影响因子
Molecular Catalysis
·
2023
·
IF 4.6
Tingting Ma,Chao Xu,Fengyang Liu,Yirong Feng,Wenyan Zhang,Weiwei Tang,Haoyu Zhang,Xiaowei Li,Yingying Nie,Shuangfei Zhao,Yuguang Li,Dong Ji,Zheng Fang,Wei He,Kai Guo
Selective epoxidation and allylic oxidation of cyclohexene were realized in the presence of BEA-Ti and (metallo)porphyrin catalysts. The integration of BEA-Ti and porphyrin H 2 MTPP afforded cyclohexene oxide with excellent selectivity (cyclohexene oxide/ 2-cyclohexen-1-one=85:15). BEA-Ti and metalloporphyrin MnMTPP yielded 2-cyclohexen-1-one with high selectivity (cyclohexene oxide/ 2-cyclohexen-1-one=12:88). Resulting active species involving of (metallo)porphyrin, Ti IV sites and tert-butyl hydroperoxide (TBHP) promoted the oxidation process of cyclohexene. A possible mechanism resulting in the formation cyclohexene oxide and 2-cyclohexen-1-one was proposed. The outer-sphere effect constructed by (metallo)porphyrin, Ti IV sites and TBHP on the surface of BEA-Ti framework improved the epoxidation and allylic oxidation both in the conversion and selectivity.
研究领域:
催化化学
·
有机合成
·
材料科学
✓ 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）