查找使用阿拉丁产品的科研文献

Effect of a novel cationic surfactant on dewaterability of activated sludge

Zhenyu Wang,Zhu Tu,Lulu Lu,Zefeng Wang,Minghua Yang

The addition of the surfactant can greatly reduce the moisture content of the sludge. But little research has been done on the synthesis of surfactants and the mechanism of dehydration. Thus, a novel cationic surfactant ZWY-28 with higher surface activity and more surface charge was investigating for sludge dewatering in this research. Results showed that when the content of ZWY-28 was 1% (0.14 g/L), the specific resistance to the filtration of sludge had a minimum value of 2.04 × 10 12 m/kg, the moisture content of the dehydrated sludge cake reached a minimum of 78.9%, the bound water reduced to 6.32 g/g, decreased by 39.2%. What’s more, the ZWY-28 is extremely helpful in releasing Extracellular polymers substances from sludge, lead to the removal of bound water, which is the key point of affecting sludge dewatering. The study clearly illustrated that the surfactant ZWY-28 accelerated the dewatering process and could be used as a potential agent for sludge. Meanwhile, it provides ideas for the selection and structure design of surfactants in sludge dewatering.

Crystal structure and up-conversion luminescence properties of K3ScF6:Er3+,Yb3+ cryolite

Dan Yang,Qingfeng Guo,Libing Liao,Yidi Zhang,Lefu Mei,Haikun Liu

In this paper, K 3 ScF 6 :Er 3+ ,Yb 3+ up-conversion luminescent materials with cryolite structure were synthesized via solid-state method. The X-ray diffraction (XRD), scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS) and photoluminescence spectroscopy (PL) under the excitation of a 980 nm laser with different power density were used to investigate the phase structure, elemental composition , and up-conversion luminescence properties of K 3 ScF 6 :Er 3+ ,Yb 3+ . The quenching concentrations of Yb 3+ and Er 3+ were confirmed to 0.15 and 0.05 (mol concentration) in this system, respectively. Upon 980 nm excitation, the K 3 ScF 6 :Er 3+ ,Yb 3+ showed a typical transition of Er 3+ which contains two main bands in the visible region that green and red. According to the fitting result of the pump power dependence of up-conversion intensity, all the green and red up-conversion emission of K 3 ScF 6 :0.05Er 3+ ,0.15 Yb 3+ belong to the two-photon process. To better understand the origin of radiation and energy transfer mechanism of the red and green up-conversion, the possible mechanism and electron transition process were also discussed.

Fabrication of high-sensitivity Bi0.2-xCexSr0.5La0.3TiO3 (0

Eggplant biomass based porous carbon for fast and efficient dye adsorption from wastewater

Zhi Liu,Xiaohai Huang,Yi Miao,Bing Gao,Yiling Shi,Jianghui Zhao,Soon Huat Tan

Adsorption techniques have been successfully applied in water purification for their simplicity, efficiency, and negligible byproducts. Porous carbon materials are effective dye adsorbents but have relatively low adsorption efficiency, slow adsorption rate, and high production cost, all of which need to be addressed for conducive practical applications. Herein, natural eggplant-based porous carbon materials (EPCMs) have been studied and successfully constructed to perform with high efficiency and fast rate of removal of dyes from wastewater. The hierarchical pore structure and well-developed mesoporous had a total pore volume of 0.6379 cm 3 /g and a maximum specific surface area of 516.0060 m 2 /g, which contributed to the high efficiency of adsorption (100%). The complete adsorption of Rhodamine B (basic and cationic dyes) solution within 25 min demonstrated its fast and high adsorption performance. The EPCMs also showed its efficiency in the absorption of various dyes, including methyl orange (acidic and anionic dye), methylene blue (basic and cationic dyes), and Yuan’qing B (reactive dye). Furthermore, the EPCMs were tested with actual wastewater from a production-based factory and recorded excellent removal effects as well, suggesting its prospective expansion for industrial applications. Therefore, this eggplant biomass-based porous carbon provides a promising approach for fast and highly efficient wastewater purification from dye-based contaminations.

Boosted photo-electro-catalytic hydrogen evolution over the MoS2/MoO2 Schottky heterojunction by accelerating photo-generated charge kinetics

Zhuangzhi Wu,Min Ouyang,Dezhi Wang,Xinli Liu

The photoelectrocatalytic water splitting of molybdenum disulfide is hindered by the intrinsic large electrical resistance among adjacent layers, serious photo-generated carrier recombination and limited utilization of visible light . Herein, we construct MoS 2 /MoO 2 heterostructures via a facile in situ hydrothermal route, in which a Schottky junction is established between the MoS 2 semiconductor and metallic MoO 2 . As a result, the photoelectrochemical current density of MoS 2 /MoO 2 is enhanced about 1.6 times than that of pure MoS 2 , achieving −10.3 mA cm −2 at −1.8 V vs. SCE, which can be attributed to the reduced electron transfer resistance, enlarged photo-generated carrier separation efficiency and enhanced light absorption due to the presence of metallic MoO 2 .

Assembly of ordered polyaniline-graphene hybrid nanomaterials based on poly(2-methoxyaniline-5-sulfonic acid) functionalized graphene nanosheets

Qiang Zhao,Junhua Chen,Fubin Luo,Lu Shen,Ying Wang,Kun Wu,Mangeng Lu

Nanostructure of ordered polyaniline-graphene (PANI-rGO PMAS ) hybrid nanomaterials is assembled based on poly(2-methoxyaniline-5-sulfonic acid) (PMAS) functionalized reduced graphene oxide (rGO PMAS ) nanosheets. The presence of PMAS not only improves dispersibility of reduced graphene oxide nanosheets, but also plays a key role for heterogeneous nucleation of polyaniline (PANI) nanorods . The formation mechanism of ordered PANI-rGO PMAS hybrid nanomaterials was studied in details by using field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM) and ultraviolet-visible spectrophotometry (UV–vis). The conductivity of PANI-rGO PMAS hybrid with 17   wt% rGO PMAS is as high as 4480   S/m, compared with 2.93   S/m for pure PANI. The cyclic voltammetry tests indicate that, PANI-rGO PMAS containing 2   wt% rGO PMAS possesses fast response to redox reactions and excellent reversible stability. It has a high specific capacitance of 385   F   g −1 at the scan rate of 10   mV   s −1 with potential ranges from −0.2 to 0.8   V. This ordered polyaniline-graphene hybrid has potential applications for flexible supercapacitors, sensors, batteries, electromagnetic materials and thermoelectric materials, etc.

A novel method to prepare Ti1.4V0.6Ni alloy covered with carbon and nanostructured Co3O4, and its good electrochemical hydrogen storage properties as negative electrode material for Ni-MH battery

Jing Lin,Lianshan Sun,Zhanyi Cao,Dongming Yin,Fei Liang,Yaoming Wu,Limin Wang

We describe our recent progress on a novel method to prepare Ti 1.4 V 0.6 Ni hydrogen storage alloy covered with nanostructured Co 3 O 4 by utilizing zelolitic imidazolate framework 67 (ZIF-67) as the template. Ti 1.4 V 0.6 Ni@C@Co 3 O 4 composite is prepared through a dopamine self-polymerization and a facile precipitation reaction with the subsequent thermal treatment. This specific composite structure combines the high conductivity of carbon together with the promising catalytic property of nanostructured Co 3 O 4 , therefore the enhanced electrochemical activity and stability are realized. As a result, Ti 1.4 V 0.6 Ni@C@Co 3 O 4 composite electrode possesses a capacity conservation rate of 56.1% after 300 charging/discharging cycles, remarkably larger than that of Ti 1.4 V 0.6 Ni (25.3%). Moreover, a study of the kinetics demonstrates that nanostructured Co 3 O 4 coating accelerates the charge-transfer reaction of the electrode. These results prove that coating with carbon and nanostructured Co 3 O 4 is a potential method for enhancing electrochemical hydrogen storage properties of hydrogen storage alloys.

Facile hydrothermally synthesis of hexagon tin disulfide nanosheets for high-performance photocatalytic hydrogen generation

Hu Yiwei,Chen Xinhang,Ren Xiaohui,Huang Zongyu,Qi Xiang,Zhong Jianxin

Tin disulfide (SnS 2 ) has been attracted intensive attention in the field of photoelectric conversion due to its appropriate band gap and glorious electronic mobility. The hexagon SnS 2 nanosheets has been successfully integrated through a facile one-pot hydrothermal method. SEM images, Raman spectra, atomic force microscope and X-ray diffraction patterns are measured to carry out to investigate the morphologies and microstructures of SnS 2 nanosheetsm, confirming a good crystallized SnS 2 . Then, the photochemical activity of as-prepared SnS 2 nanosheets were tested in the electrolyte of Na 2 SO 4 . Photoelectrochemical tests demonstrate that the photocurrent density of as-prepared hexagon SnS 2 nanosheets (1.66 µA/cm 2 at a light intensity of 140 mW/cm 2 ) is hugely increased with increasing light intensity. Furthermore, after 50 cycles, the photocurrent density does not change significantly, indicating that the as-prepared SnS 2 nanosheets possesses superior stabilities. The outstanding photocatalytic performances of SnS 2 nanosheets are not only resulted from its huge specific surface area, which can harvest more light and provide more active sites, but also attributed to its superior charge mobility, which can facilitate the separation photogenerated electron–hole pairs and the charge transfer between SnS 2 nanosheets and the electrode. The most important is that our work reveals the hexagonal SnS 2 nanosheets not only possess superior photoelectrochemical properties, but also have great potential applications in energy conversion and photodetector fields.

Constructing dimensional gradient structure of Na3V2(PO4)3/C@CNTs-WC by wolfram substitution for superior sodium storage

Shiqi Sun,Yanjun Chen,Jun Cheng,Zeyi Tian,Chao Wang,Guangping Wu,Changcheng Liu,Yanzhong Wang,Li Guo

Na 3 V 2 (PO 4 ) 3 (NVP) has gained enormous attentions due to the high capacity and voltage platform. Nevertheless, poor intrinsic electronic conductivities severely restrict the further development. Herein, a feasible strategy to construct unique dimensional gradient structure of the wolfram doped NVP is proposed via a facile sol–gel method. The introduction of W 6+ with the smaller ionic radius parallelized with local V 3+ ions could stabilize the open NASICON structure of NVP and generate vast of beneficial holes to accelerate the electronic transportation. Notably, the wolfram can combine with the superfluous carbon layer and form the new conductive WC phase to further promote the electronic conductivity. Meanwhile, the coated carbon layers and enwrapped CNTs construct an effective conductive framework for accelerated electronic migration. The twining CNTs promote to inhibit the growth of the sintered grains, reducing the particle size to provide shortened pathway for the migration of Na + . Distinctively, the modified Na 2.97 V 2.99 W 0.019 (PO 4 ) 3 /C@CNTs (W0.01-NVP) composite delivers a superior electrochemical performance. Significantly, it can submit a high reversible capability of 112.5 mAh g −1 at 5C with retaining 86% initial capacity over 500 cycles. As for a super high rate of 50C, it reveals an incredible capacity of 92.6 mAh g −1 and remains 84.5 mAh g −1 over 400 cycles, corresponding to a high retention of 91.30%. The superior electrochemical performance is derived from the enhanced crystal structure resulted from wolfram substitution and the beneficial dimensional conductive system consisting of new WC phase, coated carbon layers and enwrapped CNTs.

In-situ-derived carbon coated sea urchin-like Na3V2(PO4)3 from V2C MXene for high-performance capacitive deionization

Lanlan Yu,Ningning Liu,Baojun Liu,Fei Yu,Jie Ma

Cathode materials with high capacity and cyclic durability are urgently needed for capacitive deionization . Na 3 V 2 (PO 4 ) 3 is an emerging pseudocapacitive candidate for this process on account of its high capacity and Na + reversible insertion, while it suffers from the intrinsic low electrical conductivity and small electrolyte-accessible surface area. Herein, a sea urchin-like Na 3 V 2 (PO 4 ) 3 @carbon (NVP@C) compound material was synthesized from MXene-V 2 C via hydrothermal method followed by annealing treatment, and then assembled as capacitive deionization (CDI) electrode material . Benefiting from three-dimensional sea urchin-like structure, where the nanoneedles of NVP@C serve as fast transport channel for Na + , NVP@C performed high specific capacity (437 F g −1 at 5 mV s −1 ) and fast ionic diffusion kinetics. Moreover, the NVP@C showed attractive desalination performance as cathode material for CDI, achieving a remarkable adsorption capacity of 74.0 mg g −1 in a NaCl salt solution (1000 mg L −1 ) and long life cycle stability. The present work provides a novel perspective to construct practical redox-active and stable CDI electrode with 3D structure from MXene for highly capacitive and durable desalination application .

Tuning the morphology and structure of nanocarbons with activating agents for ultrafast ionic liquid-based supercapacitors

Yongpeng Cui,Huanlei Wang,Nan Mao,Wenhua Yu,Jing Shi,Minghua Huang,Wei Liu,Shougang Chen,Xin Wang

The increasing demand for supercapacitors with high energy and power density has attracted extensive attention in designing advanced carbon materials with high accessible surface area, hierarchical porosity , and 2D/3D morphology. Here, we report a new approach to tune the morphology and structure of the nanocarbons by using methyl cellulose as the precursor. Due to the varying effect of different activating agents, the interconnected sheet-like carbon with a high surface area of up to 2285 m 2  g −1 and a thickness down to ∼4 nm can be obtained. These important characteristics make the nanocarbons demonstrate a high capacitance of 144 F g −1 at 1 A g −1 and 20 °C, and an excellent capacitance retention ratio of 64% at 100 A g −1 in ionic liquid . Because of the high fraction of meso/macropores for nanocarbons, an outstanding capacitance of 116 F g −1 can be achieved at 0 °C, with a high capacitance retention ratio of 39% at 100 A g −1 . A high energy of 16–17 and 9–10 W h kg −1 can be maintained at 20 and 0 °C when the supercapacitor is charged in less than 1s. The excellent electrochemical response of nanocarbons suggests that the proposed preparation process is promising for developing advanced carbon electrodes.

Efficient separation of uranium in solution by ZnFe2O4 doped with TiO2: Adsorption behaviors and mechanism study

Ling Ding,Xiaolin Liu,Shuai Zhang,Jun Liao,Yong Zhang,Lin Zhang

The spinel composite doped with TiO 2 (TiO 2 @ZnFe 2 O 4 ) was prepared via in situ fabrication and template method to extract uranium(VI) from solution. Compared with ZnFe 2 O 4 and TiO 2 /ZnFe 2 O 4 , TiO 2 @ZnFe 2 O 4 showed a high adsorption efficiency (98.3%) and adsorption capacity (716.2 mg g −1 ), which mainly related to the uniform porous structure of TiO 2 @ZnFe 2 O 4 . After five adsorption–desorption cycles, the removal efficiency of TiO 2 @ZnFe 2 O 4 remained above 90%, indicating that TiO 2 @ZnFe 2 O 4 had excellent reusability. Besides, TiO 2 @ZnFe 2 O 4 possessed excellent adsorption selectivity for uranium(VI) in the existence of competitive ions. The Langmuir adsorption model and pseudo-second order model fitted well the adsorption process, which demonstrated that the remove behavior of uranium(VI) on TiO 2 @ZnFe 2 O 4 was a monolayer chemisorption process. The extraction behavior of TiO 2 @ZnFe 2 O 4 for uranium(VI) was mainly attributed to electrostatic attraction, complexation reaction and oxygen vacancy filling. This study not only provides a high efficiency adsorbent (TiO 2 @ZnFe 2 O 4 ) for the extraction of uranium(VI) from solution but also offers a new effective way to enhance the performance of spinel composite.