Energy Material Advances
·
2022
·
IF 0
Fujie Li,Chao Wang,Xiu Song Zhao
Anatase titanium dioxide (TiO2) is a potential anode material for sodium-ion batteries (NIBs). However, the low electronic conductivity and sluggish ion diffusion kinetics at high rate hamper its practical applications. Herein, we demonstrate a sol-gel approach to the synthesis of thermally stable anatase nanoparticles with a carbon shell as anode materials for NIBs. A sample calcined at 750 °C (designated as H-750TiO2@C) exhibits high-rate capability and excellent stability against cycling with no capacity loss after 2000 cycles at 1 A g-1. In situ X-ray diffraction and Raman spectroscopy characterization results reveal a nearly zero-strain characteristic of the anatase phase during charge/discharge processes. In situ transmission electron microscopy, ex situ X-ray photoelectron spectroscopy, and scanning electron microscope characterization results of samples collected at different charged and discharged states suggest that the anatase phase undergoes an irreversible sodiation-activation during the initial discharge process to form a sodiated-TiO2 phase. A full cell assembled with H-750TiO2@C as the anode and Na3V2(PO4)3 as the cathode delivers an energy density of 220 Wh kg-1, demonstrating H-750TiO2@C is a potential anode material for NIBs.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
MATERIALS RESEARCH BULLETIN
·
2018
·
IF 2.873
Zhengxia Xu,Yuhong Kan,Changqing Liu
Anatase TiO 2 nanoparticles with tuning size and aspect ratio were successfully prepared by a simple solvothermal method, using ethanol as a solvent, titanium butoxide as a precursor, and oleic acid and oleylamine as anionic and cationic capping agents, respectively. The average size and aspect ratio of these nanoparticles can be greatly regulated by varying the oleic acid/oleylamine molar ratio while keeping their total molar content constant and finely adjusted by increasing the total capping agents molar concentration in solvent at constant molar ratio (oleic acid/oleylamine molar ratio = 1:1). The variation of molar ratio or molar concentration enables a manipulation of the growth rate along different facets of TiO 2 nanoparticles and, consequently, a control of the aspect ratio of these nanoparticles. Moreover, the photocatalytic degradation rate of methyl blue for sample prepared with molar ratio of oleic acid to oleylamine at 6:24 is over 11% higher than that for the other samples.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2018
·Vol. 25
·期 31
·31250-31261
·
IF 2.8
Wang Liang,Xie Yingjuan,Liu Wenxiu,Wang Qi,Cao Wenbin
TiO 2 microstructures were synthesized via a facile one-step route for enhanced intrinsic photocatalytic performance. The prepared TiO 2 microstructures are featured by both mesoporous core-shell structures and coexposed {001}/{101} facets. Their intrinsic photocatalytic performance were remarkably enhanced due to their high specific surface area, coexposed {001}/{101} facets, and promoted separation of photogenerated carriers. Furthermore, the origin and detailed mechanism for diethylenetriamine (DETA) that served as a high efficient stabilizer of TiO 2 {001} facet have been theoretically investigated. Finally, a new DETA-modified Ostwald ripening mechanism was originally proposed when studying the growth mechanism of the mesoporous core-shell TiO 2 spherical microstructures with coexposed {001}/{101} facets.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
PubMed
高影响因子
Materials Today Energy
·
2023
·
IF 9.3
Yuhang Gao,Xu Zhang,Chaogang Ban,Ran Feng,Jixiang Hou,Jiazhi Meng,Guo Yang,Chunlang Gao,Lu Xia,Peijie Ma,Kaiwen Wang,Xianlin Qu
A typical photocatalytic H 2 O 2 production reaction primarily comprises three processes: photoabsorption, electron–hole separation and transfer, and surface oxygen reduction reaction. Previous researches have focused on revealing the origin of the facet effect in photocatalysis. However, an comprehensive understanding of the structure–activity relationship for facet effect at atomic scale remains limited. Herein, we provide fundamental insights into photocatalytic H 2 O 2 production performance of three types of TiO 2 with predominantly exposed (101), (100), or (001) facets. The TiO 2 nanosheets with exposed (001) facet exhibit the highest H 2 O 2 yield rate of 649.2 μmol g -1 h -1 , which is 29.2 and 5.2 times higher than those of TiO 2 with (101) facet and (100) facet, respectively. Band alignment, charge carrier behavior and surface reaction are studied systematically and correlated with unique surface atom arrangement. Even with narrowed light-response range, short charge carrier lifetime, inferior charge separation, and inconspicuous specific surface area, the (001) facet exposed TiO 2 still performs best. The experimental results and density functional theory (DFT) calculations reveal that the under-coordinated Ti atoms on (001) surface serve as active sites and have strong interaction with oxygen molecule, while the Ti atoms on (101) and (100) surface can hardly adsorb and activate oxygen molecule. Hence, we suggest that the significantly lowered barrier for oxygen molecule adsorption and activation results from intrinsic surface sites rather than band-alignment and charge carrier behavior plays the principal role in this case. This work may provide semiquantitative insights into the origin of facet effect in photocatalysis.
研究领域:
材料科学
·
化学
·
催化
·
表面科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2020
·
IF 8.758
Aleksei Chalgin,Wenlong Chen,Qian Xiang,Yi Wu,Fan Li,Fenglei Shi,Chengyi Song,Peng Tao,Wen Shang,Jianbo Wu
The urgent need of catalysts with improved performances toward the hydrogen evolution reaction (HER) is still one of the crucial issues for the water splitting electrocatalysis. Herein, we exhibit that the HER activity of the Pd nanocubes could be improved by selecting the appropriately shaped titania nanocrystals as support. In particular, we used Pd nanoparticles with (100)-facet exposed to show that the HER performance of Pd cubes can be improved in both acidic and alkaline electrolyte media when combined on the anatase TiO2 nanocrystals. Furthermore, we have also investigated the facet effect of TiO2 on the performance in detail, which indicated stronger catalytic activity when (001)-TiO2 was used rather than (mix 101/001)-TiO2 and (101)-TiO2. The electron-transfer-induced improvement of HER activity of Pd/TiO2 was assessed by electron energy loss spectroscopy (EELS). Thereafter, the combined support materials with suitable facet exposed can give an additional adjusting path to regulate the HER activities of Pd nanocatalysts, which henceforth can further contribute to a novel way for tuning other catalysts with good electrocatalytic properties.
研究领域:
材料科学
·
电化学
·
纳米技术
·
催化
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2018
·
IF 2.829
Chi Jiang,Weiqu Liu,Maiping Yang,Chunhua Liu,Sha He,Yankun Xie,Zhengfang Wang
We present a facile and an inexpensive approach to prepare robust fluorine-free self-cleaning cotton textiles by surface modification with anatase TiO 2 sol and polydimethylsiloxane (PDMS) using a simple dip-coating method. The synergetic effect of the anatase TiO 2 particles and PDMS was critical and essential for obtaining a superhydrophobic coating with photocatalytic activity and UV durability. The coated cotton textiles not merely exhibited desirable superhydrophobic property with a water contact angle (WCA) of 153.8°, but also performed the considerable photocatalytic activity by the decomposition of oil red O under UV exposure. Importantly, the as-obtained self-cleaning cotton textiles were stable under various harsh conditions such as acidic, alkaline, corrosive organic solutions, and laundering. Moreover, the coated cotton textiles could also maintain its superhydrophobicity when exposed to long-term UV irradiation , displaying its excellent UV resistance. Therefore, this simple preparation approach can be regarded as a promising way to construct self-cleaning surfaces for scale up production.
研究领域:
材料科学
·
纺织工程
·
表面化学
✓ 已验证
产品关联
DOI
高影响因子
WATER RESEARCH
·
2020
·
IF 9.13
Kun Li,Jin Qian,Peifang Wang,Chao Wang,Bianhe Lu,Wen Jin,Xixian He,Sijing Tang,Chao Zhang,Pan Gao
Most of the current studies on the toxicology of pristine nanoparticles (NPs) are environmentally irrelevant, because their ‘‘aging’’ process accompanied by the physicochemical transformation is inevitable in the environment. Considering aging phenomenon will gain a better understanding of the toxicity and fate of NPs in the environment. Here, we focused on the physicochemical transformation of anatase-NPs (TiO 2 -A) and rutile-NPs (TiO 2 -R) after 90 days of aging and investigated the responses of freshwater biofilm formation to the stress changes of naturally aged TiO 2 -NPs (aTiO 2 -NPs). We found that after aging, the TiO 2 -NPs underwent sophisticated physicochemical transformations in the original morphology and microstructure owing to organic and crystal salts inclusions, such as energy band changes and the formation of Ti 3+ on the NPs surfaces. These comprehensive transformations increased the stability of NPs in the exposed suspension. However, the physicochemical transformations were crystal-forms-dependent, and aging did not change the crystal structure and crystallinity . Interestingly, compared to pristine NPs, aTiO 2 -NPs showed much lower cytotoxicity and had the weaker ability to promote or inhibit the biofilm formation (p < 0.05) owing to the passivation of photoactivity caused by the comprehensive effect of the inclusions, especially for aTiO 2 -A. Regardless of aging or not of crystal forms, responses of biofilm formation were exposure-concentration-dependent, namely low concentration promotion (0.1 mg/L) and high concentration inhibition (10 mg/L), e.g., role transition of the pioneers (algae or bacteria) in initial colonization, extracellular polymeric substances (EPS) secretion and compositions of development stages with polysaccharide (PS)-rich and protein (PRO)-rich stages, and biomass and cell activity at different depths of mature biofilms. The reactive oxygen species (ROS) induced by TiO 2 -NPs showed typical hormesis. The changing trends of the autoinducers (c-di-GMP and quorum sensing signals including AHL and AI-2) were highly consistent with the growth stages of biofilms and were stimulated or suppressed by TiO 2 -NPs. The NPs crystal-dependently changed the microorganism community structures, while the UPGMA clustering of bacteria was based on the growth stages of the biofilms. The toxic mechanisms revealed that photoactivity and nanoscale retention of particles are the main reasons for the differences in the ecological stress capacity of four kinds of TiO 2 -NPs. Aging reduced characteristic differences of two pristine NPs and even reversed their relative stresses levels (p > 0.05). However, the toxicity of high-concentration aTiO 2 -NPs (10 mg/L) remained serious in a water environment. This study provides a better understanding for the water environmental risks evaluation and policy control of nanoparticles, that is, the effect of time aging has to be considered.
研究领域:
环境科学
·
纳米技术
·
生态毒理学
·
微生物学
·
水生生态学
✓ 已验证
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2020
·
IF 3.99
Qi Jiang,Jian Huang,Baoguo Ma,Zhengcai Yang,Ting Zhang,Xin Wang
TiO 2 @SiO 2 composite microspheres (TS) were prepared by the deposition of TiO 2 on the raspberry-like SiO 2 @polystyrene microspheres (PSS). The hollow microspheres with hierarchical microtopography possess both improved photocatalytic activity and stabilized TiO 2 particle structure. The results of energy dispersion spectrum (EDS) mapping, X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) showed that after calcination, anatase TiO 2 nanoparticles has formed on the raspberry-like PSS template with preferred deposition among interstitials of the drupelet-like structure. The thermal degradation of the polystyrene (PS) core during calcination led to the hollow microspheres. The photocatalytic experiments indicated that the raspberry-like TiO 2 @SiO 2 composite microspheres (TS1-TS3) had higher photocatalytic efficiency than the smooth ones (TS0), due to the hierarchical and hollow structure. The sample TS2 prepared with a moderate ammonia concentration (3 %) not only had relatively more intact hollow spherical structure, but also enhanced photocatalytic activity. The hollow TiO 2 @SiO 2 composite microspheres (TS3) prepared with 4 % ammonia showed the best photocatalytic efficiency. However, the higher ammonia concentration made the drupelet-like structure unstable and the microspheres tend to disintegrate. The raspberry-like microstructure showed a protective effect on the loaded TiO 2 , which resulted in better recyclability with persistent photocatalytic activity. The hierarchical composite microspheres shed light on the potential effective utilization strategy of nano-photocatalyst.
研究领域:
材料科学
·
化学
·
纳米技术
·
环境科学
✓ 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）