APPLIED SURFACE SCIENCE
·
2019
·
IF 5.155
Yao Zhu,Huan Yi,Qiaoyan Hao,Jidong Liu,Yuxuan Ke,Zhuo Wang,Dianyuan Fan,Wen jing Zhang
Monolayer WS 2 (1L-WS 2 ) possesses direct band gap, which is beneficial for light emitting applications. However, high quality sample obtained via mechanical exfoliation suffers from ultralow yield of large flakes while large 2D material monolayers synthesized by chemical vapour deposition (CVD) unintentionally induce many defects, resulting in low photoluminescence (PL) intensity. Herein, we firstly control the 1L-WS 2 scalable growth through H 2 introduction at the beginning of the CVD synthesis. Its domain size can be increased from 1 μm up to 20 μm with higher coverage, compared to that synthesized without H 2 introduction. Then, we propose scalable ways to anneal the obtained large 1L-WS 2 in Ar diluted hydrogen sulfide (H 2 S) atmosphere at 750 °C or to treat it with (3-mercaptopropyl) trimethoxysilane (MPS). Its PL intensity can be increased to 12 times by H 2 S or more interestingly to 30 times by MPS, respectively. Our systematic analyses show that the drastic PL improvements are mainly attributed to the reduction of structural defects by H 2 S and MPS, which is facilitated via the H– bond in them. The results help to explore routes to obtaining large-size single crystalline transition metal dichalcogenides monolayer (1L-TMDCs) and intense PL emission.
研究领域:
材料科学
·
纳米科技
·
凝聚态物理
·
表面科学
·
半导体材料
✓ 已验证
DOI
高影响因子
Desalination and Water Treatment
·
2024
·Vol. 57
·期 59
·28947-28956
·
IF 1
Qiao Wang,Guang-shan Zhang,Han Chen,Peng Wang
A specially designed combined process of pre-oxidation and nanofiltration membrane was utilized to remove As(III) in the contaminated water without reagent addition and sediment creation in this work. Different parameters that affected the rejections of As(III) and As(V) were discussed, including the initial concentration, pH of the feed, and the cross-flow filtration pressure. The rejection of As(III) was over 70% which was restricted to the high initial feed concentration, while it was around 40% under the other conditions. Whereas, the rejection of As(V) maintained above 95% in all tests. As a result, As(III) was first pre-oxidized before membrane filtration. The ozone and aeration oxidation methods were used to oxidize As(III). The effects of aeration time and oxidation time were studied. The experimental results indicated that the rejection of As(III) was increased to over 90% after pre-oxidation, and the permeate could meet the drinking water standard for As in China. Particularly, the aeration took a much longer oxidation time than ozone, but it was still a more suitable method as the pre-oxidation process because of its safety and easy operability.
研究领域:
环境工程
·
水处理技术
·
膜分离
·
污染物控制
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL GEOCHEMISTRY AND HEALTH
·
2019
·Vol. 41
·期 3
·1545-1557
·
IF 3.252
Ye Bin,Cang Yan,Li Ji,Zhang Xiaolei
Chlorine dioxide (ClO 2 ) has been widely used in the process of preoxidation and disinfection as an excellent water treatment reagent. However, the inorganic by-products produced by ClO 2 , such as chlorite (ClO 2 − ) and chlorate (ClO 3 − ) are harmful to human health, and this has become a potential problem when using ClO 2 in drinking water treatment. In this study, ClO 2 alone and a ClO 2 /NaClO combination process were carried out to evaluate the algae removal efficiency of the treatment and the formation of disinfection by-products (DBPs: chlorite, chlorate, trihalomethanes and haloacetic acids) for high algae-laden water with 124.16 µg L −1 chlorophyll a (Chl.a) content. The results show that disinfection with 1.5 mg L −1 ClO 2 alone results in a ClO 2 − concentration exceeding 0.7 mg L −1 . ClO 2 preoxidation/ClO 2 disinfection is applicable for the control of effluent quality, but the ClO 2 − concentration still has an excessive risk when using 0.8 mg L −1 and 0.6 mg L −1 ClO 2 for the two process, respectively. In the ClO 2 /NaClO combination process, the ClO 2 − concentration is below 0.6 mg L −1 , and trihalomethane (THM) and haloacetic acid (HAA) concentrations are lower than 60% of the maximum contaminant levels (MCLs) set by the World Health Organization (WHO). Further, the formation of ClO 2 − is more effectively controlled by NaClO preoxidation/ClO 2 disinfection than ClO 2 preoxidation/NaClO disinfection.
研究领域:
环境科学
·
水处理工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ELECTROCHIMICA ACTA
·
2014
·
IF 4.086
Hongjiao Nie,Yining Zhang,Wei Zhou,Jing Li,Baoshan Wu,Tao Liu,Huamin Zhang
The direct effect of nitrogen content and various nitrogen species on oxygen reduction reaction (ORR) activities in non-aqueous lithium-oxygen (Li-O 2 ) batteries are systematically investigated. Mesoporous carbon (MC) with various nitrogen species is prepared through heat treatment of N-containing precursor under different temperature. The effect of the heat treatment temperature on the performance of carbon materials in Li-O 2 battery is investigated. The bonding state of nitrogen atoms is found to have a significant effect on the ORR activity. The ORR activity in Li-O 2 battery is proved to be dependent on the quaternary N content while the total N content in the carbon material does not play a crucial role in the ORR process.
研究领域:
电化学
·
能源材料
·
纳米材料
·
电催化
·
锂离子电池
✓ 已验证
DOI
高影响因子
JOURNAL OF ELECTRONIC MATERIALS
·
2022
·Vol. 51
·期 9
·4846-4854
·
IF 2.047
Bo Lin,Wang Lei,Hou Yangbo,Li Fujin,Liu Sida,Zhang Ruipeng,Zuo Min,Zhao Degang
Ternary Cu 3 SbSe 4 thermoelectric material with a diamond-like structure exhibits good thermoelectric performance in the middle-temperature region. In this study, Cu 2.98 Co 0.02 SbSe 4 material with intrinsically low thermal conductivity was prepared by a melting–ball milling–hot pressing process. The maximum zT value for the Cu 2.98 Co 0.02 SbSe 4 sample was 0.7 at 650 K, which was about 190% higher than that of the pristine sample. The improvement in thermoelectric performance was ascribed to the realization of multi-scale features induced by ball milling. It was found that multiple scattering centers of phonons were formed via interfacial engineering, including dislocations, nano-holes and grain boundaries, which offers an applicable pathway for the reduction of lattice thermal conductivity. Graphical
研究领域:
材料科学
·
凝聚态物理
·
功能材料
·
能源材料
·
半导体物理
✓ 已验证
DOI
高影响因子
PRECISION ENGINEERING-JOURNAL OF THE INTERNATIONAL SOCIETIES FOR PRECISION ENGINEERING AND NANOTECHNOLOGY
·
2016
·
IF 1.914
Kun Shan,Ping Zhou,Yunsheng Zuo,Renke Kang,Dongming Guo
Electrogenerated chemical polishing (EGCP) had been proved effective in improving both the smoothness and the flatness of copper surface in our previous work. In this paper the polishing ability, defined as the ratio between the material removal rate at the peak and at the valley of a rough surface, is studied theoretically and experimentally. In a mathematical model, the effects of the special wavelength L , the peak-to-valley height h of the workpiece surface profile and the working distance d between working electrode and workpiece surface on the polishing ability are studied. The results show that the polishing ability decreases with increasing the working distance and finally approaches the value ( d + h )/ d , if L is much larger than d . However, the effect of the working distance on polishing ability is negligible, if L is close to or less than d . The polishing ability also decreases with h decreasing. Based on the above analysis, an analytical expression of the polishing ability of EGCP is given. For validating the theoretical analysis, a copper surface is polished by EGCP and the change of the surface profile is measured and analyzed using the analytical expression. The measured polishing ability agrees well with the simulation results.
研究领域:
材料科学
·
表面工程
·
电化学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2021
·
IF 6.707
Huaxia Li,Wencui Chai,Yijun Cao,Shichong Yang
Surface pretreatment on minerals prior to flotation was proved to increase the selectivity of separation process. Organic acid pretreatment of low-grade diasporic-bauxite was conducted, and the effects of oxalic acid on bauxite flotation were investigated in this work. The oxalic acid pretreatment mechanisms were studied by adsorption measurements, zeta potential testing, XPS analysis, and ICP analysis. The flotation results showed that the oxalic acid treatment could significantly improve Al 2 O 3 recovery from 75.39% to 81.88% and decrease SiO 2 recovery from 53.26% to 47.30%. The adsorption capacity of diaspore for sodium oleate (NaOL) increased by 8.50%, while that of kaolinite decreased by 11.72%. XPS analysis revealed that oxalic acid treatment improved the relative contents of unsaturated Al at diaspore surface beneficial to the adsorption of NaOL. While the relative content of Al at kaolinite surface was decreased due to the Al dissolution revealed by ICP results. Zeta potential analysis indicated that oxalic acid changed the surface property of minerals favorable for the selective adsorption of NaOL on diaspore surface rather than kaolinite surface. These findings provided a promising direction for surface pretreatment of low-grade bauxite using oxalic acid for the improvement of the flotation desilication.
研究领域:
矿物加工工程
·
表面化学
·
资源综合利用
·
浮选化学
·
冶金工程
✓ 已验证
DOI
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2019
·
IF 2.291
Zhuo Dai Li,Huai Qiang Zhang,Xiao Hong Xiong,Feng Luo
Covalent organic frameworks (COFs) represent an exciting new type of porous organic materials, which are constructed with organic building units via strong covalent bonds . Here in, the COF-2,4,6-Triformylphloroglucinol p-Phenylenediamine (COF-TpPa-1) was synthesized by solvothermal method for the removal of U(VI) from aqueous solution. Effects of pH, adsorption dose, contact time, uranium solution concentration, temperature and adsorption and desorption cycle on the efficiency of COF-TpPa-1 removal of U(VI) are investigated. SEM, XRD , TGA and FT-IR were employed to characterize the samples and analyze adsorption mechanism. The results manifested COF-TpPa-1 has the high adsorption capacity ( q m = 152 mg/g), quick adsorption kinetic , high selectivity , outstanding recycle performance and good resistance to acids, bases and high temperature.
研究领域:
环境化学
·
材料科学
·
核化学
·
污染治理
·
吸附科学
✓ 已验证
DOI
高影响因子
Journal of Energy Storage
·
2021
·
IF 6.583
Tiantian Zhang,Shi Juan,Wang Yi,Zhenqian Chen
Halloysite nanotube (HNT), a natural and environmentally friendly low-cost material with significant reserves, has become one of promising candidates for preparation of form-stable composite PCM with satisfactory thermal properties owing to their hollow tubule structure and high surface area. The present work prepared the form-stable composite with HNTs and acid etching HNTs (A-HNTs) and compares the properties closely related to thermal energy storage application. Specifically, the micromorphology, thermal properties, shape-stabilized properties, as well as thermal conductivities of the composite materials were characterized by utilizing SEM, TEM, FTIR, DSC, BET, and Hot-disk wire methods, respectively. The results showed that the n-octadecane can both adhere on the inner lumen and the outer wall of HNTs and A-HNTs, while the A-HNTs possess significantly improved absorption thanks to the fact that the pore volume of A-HNTs was enlarged by 19.2% in comparison with HNT, which empowers the extra 5.8% phase transition enthalpy of n-octadecane@A-HNT. In addition, the composite PCMs have a good long-term thermal stability based on multi-cycle heat absorption and release further highlights the potentials in thermal storage application.
研究领域:
材料科学
·
纳米科技
·
能源材料
·
热力学
·
环境友好材料
✓ 已验证
DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2024
·Vol. 35
·期 5
·e6421
·
IF 3.1
Ya-Jing Cao,Xue-Jie Gai,Wei Li,Hai-Hui Liu,Na Han,Xing-Xiang Zhang
Artificial muscles have attracted great attention as actuators and coiled and twisted monofilament actuators are considered the most promising ones. In the present work, the torsional properties of poly(hexamethylene adipamide) (PA66), poly(ethylene terephthalate) (PET), and high-strength PET (HTPET) monofilaments were investigated. Furthermore, cross-linked PET (CPET) monofilaments were melt-spun by adding 1 wt% of 2-dimethoxy-2-phenylacetophenone (ultraviolet (UV) initiator) and triallyl iso-cyanurate (cross-linking agent) in PET chips under UV radiation. The HTPET monofilaments had the highest torsional modulus of 1.1 GPa followed by the PET (0.8 GPa) and PA66 (0.6 GPa) monofilaments. Subsequently, the HTPET monofilaments were subjected to heat treatments under tension. When the heat treatment time was 10 min, the mechanical properties of the HTPET monofilaments also tended to first increase and then decrease with the rise of heat treatment temperature. The molecular arrangement and crystal structure of the HTPET monofilaments were gradually improved with the prolongation of tension heat treatment. The tensile strength and initial modulus of the HTPET monofilaments were 871.4 MPa and 15.8 GPa, respectively. The mechanical properties of the CPET monofilaments first increased and then decreased with the increase of the drawing ratio. When the drawing ratio was 10, the CPET monofilament had a tensile strength of 717.2 MPa, an initial modulus of 16.7 GPa, and a maximum torsional modulus of 1.3 GPa. Therefore, both heat treatment and cross-linking increased the mechanical strength of the PET monofilaments. CPET and HTPET are possible to be used as artificial muscles.
研究领域:
材料科学
·
高分子物理
·
纺织工程
·
生物医学工程
·
智能材料
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2018
·
IF 2.829
Yueyun Fang,Qizhang Huang,Pengyi Liu,Jifu Shi,Gang Xu
This study demonstrated high-efficient dye adsorption for wastewater using MoS 2 -glue sponge as an easy-separative and regenerative adsorbent. Flower-like molybdenum disulfide (MoS 2 ) nanopowders with rich polar edge sites were firstly synthesized by a facile one-pot hydrothermal method . Chemical and morphological features of MoS 2 nanoflowers were then examined by XRD , XPS , SEM and TEM . Afterwards, different concentrations of the MoS 2 -glue sponges with easy separability were successfully fabricated by a convenient two-step dip-coating method. The adsorption performance was estimated by the removal of Rhodamine B (RhB) dyes. The results proved that the maximum adsorption capacity of MoS 2 -glue sponge was 127.39 mg RhB/g product in 60 min. The RhB uptake behaviors can be well described by the Sips isotherm model and pseudo-second-order kinetic model , indicating a multilayer and chemical adsorption process. The adsorption mechanism proposed that the zwitterionic RhB molecules in aqueous solution would aggregate on the surface of negative charged MoS 2 in a head-to-tail way through electrostatic interaction . Furthermore, RhB dyes could desorb easily from MoS 2 -glue sponges when changing the polarity of solvent and the reusability experiment showed that the MoS 2 -3% glue sponge could be reused for 15 times with above 85.8% of the adsorption capacity retained. Thus, the novel MoS 2 -glue sponge is considered as a competitive adsorbent for treatment of dyestuff waste water.
研究领域:
环境科学
·
材料科学
·
纳米技术
·
化学工程
·
水污染控制
✓ 已验证
DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 118
·97435-97445
·
IF 3.84
Yuling Cai,Liuchun Zheng,Zhanqiang Fang
To reduce costs and improve practicability, an ion imprinted magnetic chitosan (IMCS) was synthesized through co-precipitation using steel pickling waste liquor and chitosan and Cu(II) as template ions, which was then characterized by TEM, SEM, EDX, FTIR, XRD and VSM. The batch experiments were carried out for its potential application and high selectivity of Cu(II) removal, which were observed due to the paramagnetic properties and coordination reactions in the imprinted cavities. Kinetic studies revealed that the adsorption process followed a pseudo second-order model and the equilibrium data fit perfectly with the Langmuir isotherm model. The maximum adsorption capacity was 109.89 mg g−1. Negative values for ΔH0 and ΔG0 indicated an exothermic and spontaneous adsorption process. The adsorption process was found to be a chemical reaction and coordination complexes were formed between the metal ions and the groups of chitosan binding mainly in the “bridge model”. Moreover, 0.2 mol L−1 HCl solution was considered as the most appropriate eluent for regeneration. It showed a great performance in the experiments for practical copper wastewater and the process was considerably cost-effective.
研究领域:
环境化学
·
材料科学
·
污染控制工程
·
资源循环利用
·
吸附技术
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）