PLoS One
·
2024
·Vol. 19
·期 8
·e0306866
·
IF 2.9
Yan Cheng,Ke Wang,Siyi Zhang
Low-dimensional materials have demonstrated strong potential for use in diverse flexible strain sensors for wearable electronic device applications. However, the limited contact area in the sensing layer, caused by the low specific surface area of typical nanomaterials, hinders the pursuit of high-performance strain-sensor applications. Herein, we report an efficient method for synthesizing TiO 2 -based nanocomposite materials by directly using industrial raw materials with ultrahigh specific surface areas that can be used for strain sensors. A kinetic study of the self-seeded thermal hydrolysis sulfate process was conducted for the controllable synthesis of pure TiO 2 and related TiO 2 /graphene composites. The hydrolysis readily modified the crystal form and morphology of the prepared TiO 2 nanoparticles, and the prepared composite samples possessed a uniform nanoporous structure. Experiments demonstrated that the TiO 2 /graphene composite can be used in strain sensors with a maximum Gauge factor of 252. In addition, the TiO 2 /graphene composite-based strain sensor showed high stability by continuously operating over 1,000 loading cycles and aging tests over three months. It also shows that the fabricated strain sensors have the potential for human voice recognition by characterizing letters, words, and musical tones.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL
·
2015
·
IF 3.615
Jian Wang,Xue Wang,Xiaolong Liu,Junlin Zeng,Yangyang Guo,Tingyu Zhu
In this article, we present a detailed study combining the kinetic studies and in-situ FTIR experiments to investigate the oxidation behavior of chlorobenzene over V 2 O 5 /TiO 2 catalysts. The catalytic data show the 3–5 wt.% V 2 O 5 /TiO 2 catalysts are best fit for the oxidation of chlorobenzene. The calculated apparent reaction orders are about 0.6 and 0.2, respectively. The results of in-situ FTIR provided mechanism insights into the catalytic reaction, which supports the following proposal: (i) a nucleophilic substitution on V O species and (ii) attacking by surface oxygen through a electrophilic substitution, then (iii) followed by the cracking of ring structure, and further oxidation of the resulting species to form final products. The above results further suggest that the nucleophilic substitution process and surface reaction are kinetically significant steps for chlorobenzene oxidation, determining the overall rate of the reaction. Furthermore, 1,2-dichlorobenzene, 1,3-dichlorobenzene and 1,2,4-trichlorobenzene as additional reactants were tested together with chlorobenzene in binary mixtures to examine their competition reactions.
研究领域:
环境科学
·
催化化学
✓ 已验证
DOI
高影响因子
OPTICAL MATERIALS
·
2022
·
IF 3.754
Bo Zhang,Jie Luo,Zhi Chen,Yuanshun Xiang,Lu Tang,Hongyi Jiang,Yuanyuan Tian,Shengli Liu
The development of high-quality cathode material is of important value to the research of bifunctional electrochromic energy storage device. Therefore, Nb-doped TiO 2 mesoporous film as the high-performance cathode was prepared via a facile sol-gel technology successfully. The Nb doping content has great effects on the crystallinity and chemical state of TiO 2 films. Compared to the pure TiO 2 film, the optimum Nb-doped TiO 2 film exhibits the excellent optical-electrochemical performance including highest large-rate capability, largest specific capacity (62.4 mAh/g), short switching time (3.4 s/4.5 s) and large transmittance modulation (50.7%). These data indicate that Nb-doped TiO 2 mesoporous films possess the important application prospect.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
Inorganic Chemistry Frontiers
·
2023
·Vol. 10
·期 4
·1176-1186
·
IF 7
Yue Xu,Yang Li,Yong Qian,Shanshan Sun,Ning Lin,Yitai Qian
Silicon monoxide (SiO) is regarded as a promising material to replace traditional graphite anode in the next generation lithium-ion batteries. However, the huge volume expansion and poor ionic/electronic conductivity of SiO particles largely restrict its application in the fast charging and discharging process. Herein, a deficient TiO2−x coated porous SiO structure was designed through the Ag-assisted chemical etching process followed by a hydrolysis approach. Within this composite, the internal pores of SiO particles could accommodate the irregular volume change and also shorten the diffusion pathway of lithium ions. Moreover, the outer TiO2−x could provide a protective shell and favor the generation of stable SEI films. In addition, the large specific surface area increases surface active sites and promotes the electrochemical reaction of lithium ions during the high-rate lithiation/de-lithiation process. As a result, the synthesized porous SiO/TiO2−x composites delivered a high capacity of 501.2 mA h g−1 with a capacity retention of 52.41% at a current density of 1.0 A g−1 after 300 cycles. Even at 2.0 A g−1, it maintained a reversible capacity of 423.4 mA h g−1 after 500 cycles. Finally, a full cell composed of porous SiO/TiO2−x composites and commercial LiCoO2 presented a distinctive enhancement in energy density compared with that of a pure SiO anode. A series of characterization analyses and electrochemical measurements were performed to disclose the mechanism for the superb performance of materials.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
CATALYSIS LETTERS
·
2022
·Vol. 152
·期 11
·3453-3464
·
IF 2.936
Zhao Mengqi,Pan Zhiquan,Chen Qingrong,Zhou Hong
Diosgenin is an important intermediate of drugs, the special structure similar to hormone determines its important position in drug synthesis. Diosgenin was generally obtained by sulfuric acid hydrolysis of dioscorea, which produced too much acid wastewater, and caused environmental issues. A new solid acid based on TiO 2 was designed and synthesized through the sulfonation of the prepared TiO 2 , the structure was fully characterized by FTIR, SEM, EDX, XPS and XRD. Under the optimized conditions, the yield of diosgenin reached 30.75%, the value was much higher than that of H 2 SO 4 of the same quality. To explore the factors that affect the yield, the usage amount of the solid acid, the temperature, the solvent volume and the extraction time were taken into the analysis, and the results of the recycling experiments indicated that the prepared solid acid can be used for three time and maintain its high activity. A highly efficient solid acid catalyst for diosgenin extraction from saponins was successfully synthesized, and the extraction method was environmentally friendly. Graphical Abstract
研究领域:
药物化学
·
环境科学
✓ 已验证
DOI
高影响因子
Nanomaterials
·
2020
·Vol. 11
·期 1
·60
·
IF 4.324
Xiong Wang,Wenqian Kang,Lin Gao,Guangquan Li,Xuerong Chen,Yi Guo
Porous organic polymers (POPs) have proven to be an efficient support in the olefin polymerization catalyst field. In this paper, nano TiO2beads were used to modulate the pore structure, bulk density, and surface morphology and flowability of the prepared POPs. With the incorporation of the hydrophilic nano TiO2beads, the prepared TiO2/POP supports obtained reasonable specific surface area (100–300 m2/g) and higher bulk density (0.26–0.35 g/mL) and flowability than the pure POP supports. The results show that bulk density of the prepared TiO2/POP particles increased when adding an increased amount of TiO2, and when 37.5% TiO2(weight percent to the total comonomers divinylbenzene (DVB) and 2-hydroxyethyl methacrylate (HEMA)) and 3:1 DVB/HEMA (molar ratio) were added, highly flowable TiO2/POP composites (POP-6 and POP-7) were obtained. With the modulation of the nano TiO2template during the support synthesis, the prepared POP-7 particles successfully achieved a normal distribution with a narrow particle size distribution (PSD) of 0.717 and average particle size of 24.1 μm, a specific surface area (SSA) of 279 m2/g, and relatively high bulk density of 0.30 g/mL. Furthermore, all the prepared TiO2/POP supports obtained higher ethylene polymerization activity than silica gel-supported commercial metallocene catalyst. The immobilized (n-BuCp)2ZrCl2/MAO@POP-7 catalyst exhibited the highest ethylene polymerization activity of 4794 kg PE/mol Zr.bar.h and productivity of 389 g PE/g cat, more than twice that of the commercial counterpart. Even higher catalyst productivity (3197 g PE/g cat) and bulk density of the produced PE (0.36 g/mL) could be obtained in higher ethylene partial pressure at 80 °C for 2 h, and the prepared TiO2/POP catalyst shows no obvious Zr+active sites decay during the ethylene polymerization.
研究领域:
材料科学
·
催化化学
✓ 已验证
DOI
高影响因子
ACS Applied Polymer Materials
·
2024
·
IF 4.4
Yang Han,Xude Qin,Qianqian Kang,Weijie Fan,Dongxiao Han,Yantong Pei,Ye Chen,Wei Wang
Self-healing coating technology is an emerging strategy for extending the longevity of anticorrosion coating. Nevertheless, a significant challenge lies in ensuring that the coating can endure multiple cycles in intricate environments while sustaining a stable mechanical performance. In this study, we prepared a TiO2/Ti3C2Tx/PDMS elastomer coating by incorporating Ti3C2Tx nanosheets to improve mechanical properties and enhance physical barrier performance through photografting. Compared to PDMS without TiO2/Ti3C2Tx, the tensile strength increased from 10.32 to 16.24 MPa. Even after undergoing multiple loading–unloading cycles, the elastomer retained 88.98% of its initial strength, demonstrating remarkable durability and self-healing capabilities. Due to the presence of dynamic disulfide bonds, the coating can undergo a self-healing process within 30 min under 60 °C heating conditions. Furthermore, the presence of TiO2/Ti3C2Tx modified through photografting enhanced hydrophobicity and formed a micro/nanolayered “maze effect” structure, establishing a passive anticorrosion mechanism. This structure demonstrated sustained corrosion resistance for up to 50 days in aggressive environments, effectively preventing the corrosive medium from compromising the metal substrate.
研究领域:
材料科学
·
腐蚀与防护
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Communications
·
2024
·
IF 3.7
Hanqing Zhao,Lingyu Meng,Feiyu Wang,Irfan,Ming Hu
Powder preparation is the key step in producing laser cladding coatings with desired properties. In this paper, quaternary TiO 2 -B 4 C-C-Cu composite powder with high sphericity and good densification has been successfully prepared by a powder fabrication process combining spray granulation with densification sintering. The effects of slurry characteristics, spray granulation process parameters, and densification sintering temperature on particle morphology and performance were studied. The formation mechanism of quaternary spherical TiO 2 -B 4 C-C-Cu composite powder was revealed by analyzing the process of heat transfer and water transfer in the droplets, and the optimization direction of the powder preparation was indicated. The optimized process parameters for the quaternary spherical TiO 2 -B 4 C-C-Cu composite powder are: slurry solid content of 52 wt%, dispersant content of 1.25 wt%, binder content of 2 wt%, inlet temperature of 180 °C, the airflow rate of 310 L/h, slurry feed rate of 4.5 ml/min, and the two-stage temperatures of densification sintering are 500 ℃ and 900 ℃ for 1 h, in turn. Under the optimized process, the fluidity of the powder reaches 112 s/50 g, the apparent density reaches 1.2 g/ml, and more than 70% of the particles are between 15–53 µm. The powder has been verified by laser cladding to prepare in-situ synthesized TiB 2 -TiC-Cu composite coatings , which could have a better prospect for potential application.
研究领域:
材料科学
·
表面工程
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2021
·
IF 19.503
Zhi-Wen Wang,Qiang Wan,Ying-Zhang Shi,Huan Wang,Yue-Yue Kang,Shu-Ying Zhu,Sen Lin,Ling Wu
Ultrathin TiO 2 nanosheet (NST) with abundant Ti 3+ sites is developed as a photocatalyst which exhibits a high yield (147.2 μmol g −1 h −1 ) and selectivity (96.8%) for CO 2 to CH 4 . The results of in situ FTIR, in situ EPR and density functional theory (DFT) calculation suggest that CO 2 would be selectively activated on NST surface via forming the bridging Ti···CO 2 − ···Ti coordination species which not only lowers the activation energy barrier, but also determines the selectivity of CH 4 . Additionally, NST with the better separation and transfer ability for photogenerated electrons-holes can fleetly supply the electrons to CO 2 molecules for high efficiently producing CH 4 via the Ti-C coordination bond. Finally, a possible mechanism of the synergistic effect about coordination-activation and photocatalysis is discussed at a molecule level. This work would offer a perspective for designing an effective photocatalyst and tailoring the selectivity of products by coordination activation.
研究领域:
材料科学
·
环境科学
·
化学
✓ 已验证
DOI
高影响因子
ACTA PHYSICO-CHIMICA SINICA
·
2024
·
IF 10.8
Zhuoyan Lv,Yangming Ding,Leilei Kang,Lin Li,Xiao Yan Liu,Aiqin Wang,Tao Zhang
Direct epoxidation of propylene (DEP) by molecular oxygen is an ideal way to synthesize propylene oxide (PO), yet it remains quite challenging. We demonstrated here that the PO formation rate and selectivity could be enhanced simultaneously through photo-thermo-catalysis over the CuO x /TiO 2 catalyst. At 180 °C, by introducing light, the PO formation rate increased more than 20-fold (from 8.2 to 180.6 μmol g −1 h −1 ) and the corresponding selectivity improved more than 3-fold (from 8 % to 27 %), breaking the traditional perception that the semiconductors exhibit very low reactivity for this reaction. Kinetic study results showed that the apparent activation energy for PO formation could sharply decrease under light irradiation (from 95 to 40 kJ mol −1 ). In situ electron paramagnetic resonance (EPR), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) were applied to characterize the dynamics of the valence state of the copper oxide species and the activation intermediates of molecular oxygen. Evidence for the activation of oxygen, which could direct to the PO formation pathway, was captured. The light-driven electrons could promote the formation of active Cu + , which could form the side-on μ-peroxo Cu(II) 2 structure, weaken the O–O bond, and improve the PO formation rate and selectivity. This work paves a new way for designing semiconductor-supported photocatalysts for DEP reactions with molecular oxygen.
研究领域:
化学工程
·
催化科学
✓ 已验证
DOI
高影响因子
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
·
2018
·
IF 2.593
He Lian,Zhaoxu Meng
Over the past years, the high catalytic property of electrospun nanofibers attracted more attention in the field of catalysis. Titanium dioxide (TiO 2 ) electrospun nanofibers and their modifications have become the focus of the photocatalysis research owing to their high surface to volume ratio, high porosity and non-toxicity. So far, however, it has not been applied in the photocatalytic devices because the bad self-supporting is still the main drawback to prevent their practical application. Here, a novel three-dimensional porous membrane of hybrid TiO 2 /bioglass, which could be adhered on different carriers as “wallpaper” only by a short time of heating, has been fabricated in this work. Though microfluidic electrospinning, the hybrid nanofibrous membrane could be divided into three thin layers according to the components of the fiber. The top layer of the hybrid nanofibrous membrane, containing 90% TiO 2 in the fiber, would maintain three-dimensional interconnected porous structure with the increasing of its thickness, revealing highly photocatalytic activity . In addition, the bottom bioglass (70SiO 2 ·25CaO·5P 2 O 5 ) nanofibrous layer of the hybrid TiO 2 /bioglass membrane made the membrane adhere on different carriers firmly through heating within 5 s. The hybrid membrane exhibited higher photocatalytic efficiency than the thin film of TiO 2 , which would be expected to be used in the preparation of photocatalytic devices.
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
MATERIALS RESEARCH BULLETIN
·
2018
·
IF 2.873
Tianyu Zhao,Zipeng Xing,Ziyuan Xiu,Zhenzi Li,Liyan Shen,Yan Cao,Mengqiao Hu,Shilin Yang,Wei Zhou
CdS quantum dots (QDs)/Ti 3+ -TiO 2 nanobelts heterojunctions as 0D/1D architectures are fabricated through hydrothermal-chemical bath deposition combine with in-situ solid-state chemical reduction approach. The CdS QDs of ∼7 nm are loaded on TiO 2 nanobelts with width of 50–300 nm and several micrometers long, and the heterojunctions are formed efficiently. The prepared heterojunctions exhibit excellent photocatalytic performance for complete removal of methylene blue (∼99%) and hydrogen production efficiency (∼480.6 μmol h −1 ) under visible light irradiation, which are as high as 2 and 23 times than that of pristine TiO 2 nanobelts. The enhancement is attributed to the Ti 3+ self-doping and CdS QDs extend the photoresponse to visible light region and the formation of heterojunctions favor the spatial separation of photogenerated charge carriers. Therefore, the high-efficient 0D/1D heterojunction composites have potential applications in the field of environment and energy.
研究领域:
材料科学
·
环境科学
·
能源科学
✓ 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）