共查询到20条相似文献,搜索用时 15 毫秒
1.
2.
From a materials science point of view, graphene is essentially a polymer having a giant, two‐dimensional molecular configuration. In this Progress Report, solvated graphene and its derivatives are illustrated from the perspective of soft matter. Firstly, the key appealing features of graphene as a molecular building block for assembling bulk soft materials are highlighed. It is then demonstrated how the intersheet interactions in solution are correlated with the molecular structure of graphene, and how a combination of the unique molecular structure and colloidal interactions can lead to simple, solution‐phase approaches for assembling graphenes into a variety of macroscopic nanoarchitectures. A number of new exciting functions and applications are also highlighted, which are enabled by the solvation effect and in particular, it is discussed why and how solvated graphenes can offer exciting functions that are unattainable with the dried, hard counterpart. The discussion is concluded with some personal perspectives on the future directions in which this emerging class of functional soft materials could be pursued. 相似文献
3.
采用水热合成法与原位分解法相结合, 在不使用软模板和强碱条件下制备得到了米粒状氧化铜(CuO)。将得到的CuO材料与Nafion溶液混合, 制作成化学修饰电极(CME), 开展葡萄糖的无酶检测。采用X射线衍射仪(XRD)和扫描电子显微镜(SEM)分别对所制备的材料和电极的结构、形貌进行表征、分析。采用线性扫描伏安法、循环伏安法、安培响应和交流阻抗技术对所制备电极进行电化学性能测试。研究结果表明: 所制备的CuO形貌在微观下酷似米粒, 长度为0.5~ 1.0 μm, 直径为250~320 nm。当CuO修饰量为0.35 mg (电极表面积为0.22 cm2)时, 修饰电极对葡萄糖具有较好的电化学检测性能。在0.0357~2.361 mmol/L浓度范围内存在良好的线性关系, 其线性方程为: Ipa(mA)= -0.00187+0.05239c (mmol/L), R2=0.998。检出限为 0.0647 μmol/L, 灵敏度为950.36 μA·L/(mmol·cm2), 且具有良好的选择性和可靠性。 相似文献
4.
Hong Yu Yonghui Wang Yao Jing Jianmin Ma Cheng‐Feng Du Qingyu Yan 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(25)
In recent years, the rapidly growing attention on MXenes makes the material a rising star in the 2D materials family. Although most researchers' interests are still focused on the properties of bare MXenes, little attention has been paid to the surface chemistry of MXenes and MXene‐based nanocomposites. To this end, this Review offers a comprehensive discussion on surface modified MXene‐based nanocomposites for energy conversion and storage (ECS) applications. Based on the structure and reaction mechanism, the related synthesis methods toward MXenes are briefly summarized. After the discussion of existing surface modification techniques, the surface modified MXene‐based nanocomposites and their inherent chemical principles are presented. Finally, the application of these surface modified nanocomposites for supercapacitors (SCs), lithium/sodium–ion batteries (LIBs/SIBs), and electrocatalytic water splitting is discussed. The challenges and prospects of MXene‐based nanocomposites for future ECS applications are also presented. 相似文献
5.
6.
通过恒电压沉积法将纳米金属镍沉积于石墨电极表面, 经化学气相沉积法在石墨电极表面原位生长出碳纳米管(CNTs), 通过电化学聚合法在CNTs表面原位聚合聚苯胺, 从而获得化学修饰电极。采用扫描电子显微镜对所得电极形貌结构进行表征, 并研究CNTs与PNAI复合电极对抗坏血酸(AA)的检测效果。研究结果表明: 制备的CNTs都能均匀地生长在石墨电极表面, 纳米中空管状结构都保持完好; PANI均匀地包覆在CNTs管壁上, 复合材料呈现出典型的三维网状结构。所制备的CNTs/PANI修饰电极对AA具有良好的电化学响应, 其中管径较小CNTs的修饰电极对AA的电化学响应更强: 具有更宽的检测范围和更低的检出限。其检测线性范围为1.0×10-6~4.5×10-4 mol/L, 检出限为1.0×10-7 mol/L (S/N = 3)。且具有良好的稳定性、重复性和可靠性。 相似文献
7.
8.
Maxim K. Rabchinskii Vladimir V. Shnitov Dina Yu. Stolyarova Sergei A. Ryzhkov Marina V. Baidakova Eugenia Yu. Lobanova 《Fullerenes, Nanotubes and Carbon Nanostructures》2020,28(3):221-225
AbstractThe one-step method for graphene oxide (GO) simultaneous reduction and carboxylation via ultraviolet irradiation in the inert atmosphere has been reported. X-ray photoelectron spectroscopy (XPS) and X-ray absorption spectroscopy (XAS) data revealed that the proposed approach allows to obtain reduced graphene oxide (rGO) films, containing up to 10 at.% of carboxyl groups. The carboxyl groups concentration can be tuned within the range of 3 to 10 at.% by controlling the oxidation degree of the irradiated GO via the preliminary low-temperature air heating. Furthermore, no carboxylation effect is observed in the case of irradiation of the completely reduced GO films. This coincides with our previous results, validating the proposed model of GO carboxylation based on photoinduced conversion of basal-plane hydroxyl groups and ketones into carboxyl ones. Despite a different degree of carboxylation, all the obtained samples demonstrate almost complete elimination of basal plane groups and restoration of the graphene flakes aromatic structure. This fact is emphasized by the sheet resistance measurements, demonstrating that the obtained C-xy graphene exhibits high electrical conductivity. As a net result, the material obtained by the presented method shows promising applications in the manufacturing of biosensor transducers owing to both its conductive nature and presence of carboxyl groups, playing the role of the anchoring points for biomolecules. 相似文献
9.
城市污水厂污泥改性物对Hg(Ⅱ)吸附的研究 总被引:1,自引:0,他引:1
以城市污水处理厂活性污泥为原料,制取干污泥,并将其和化学改性污泥作为吸附剂,对含Hg(Ⅱ)离子的废水进行了吸附试验研究.考察了溶液pH值、吸附剂用量和Hg(Ⅱ)离子的初始浓度对去除率的影响.结果表明,干污泥及其化学改性污泥吸附剂对Hg(Ⅱ)离子的吸附符合Lagergren一级动力学方程.在试验条件下,化学改性污泥的相对吸附量高于干污泥,因此,活性污泥经过化学改性后能够提高对Hg(Ⅱ)离子的吸附能力.用0.1mol/L HNO3溶液进行超声解吸附,Hg(Ⅱ)离子的回收率可达70%左右.利用这种吸附剂可以有效地去除工业废水中的Hg(Ⅱ)离子. 相似文献
10.
A Solution‐Processed High‐Performance Phototransistor based on a Perovskite Composite with Chemically Modified Graphenes 下载免费PDF全文
Liu Qian Yilin Sun Mingmao Wu Dan Xie Liming Ding Gaoquan Shi 《Advanced materials (Deerfield Beach, Fla.)》2017,29(22)
Phototransistors with a structure of a nitrogen‐doped graphene quantum dots (NGQDs)–perovskite composite layer and a mildly reduced graphene oxide (mrGO) layer are fabricated through a solution‐processing method. This hybrid phototransistor exhibits broad detection range (from 365 to 940 nm), high photoresponsivity (1.92 × 104 A W?1), and rapid response to light on–off (≈10 ms). NGQDs offer an effective and fast path for electron transfer from the perovskite to the mrGO, resulting in the improvement of photocurrent and photoswitching characteristics. The high photoresponsivity can also be ascribed to a photogating effect in the device. In addition, the phototransistor shows good stability with poly(methyl methacrylate) encapsulation, and can maintain 85% of its initial performance for 20 d in ambient air. 相似文献
11.
12.
13.
目的 研究自发气调处理对采后软枣猕猴桃果实品质的影响。方法 将软枣猕猴桃置于塑料气调箱内,气调处理组果实放入气调箱封盖处理,对照组进行不封盖处理,于4 ℃下贮藏64 d,每16 d对软枣猕猴桃呼吸代谢及抗性相关指标进行测定,即气调箱内CO2和O2含量,可溶性固形物(TSS)、丙二醛(MDA)、总酚含量,及抗氧化相关酶活性等指标。结果 自发气调处理能够使CO2和O2含量维持在适宜的贮藏范围内,从而保持较高的TSS和总酚含量,抑制MDA含量及多酚氧化酶(PPO)活性,增强过氧化物酶(POD)、苯丙氨酸解氨酶(PAL)和过氧化氢酶(CAT)活性。结论 贮藏48~64 d,自发气调处理软枣猕猴桃的最适宜气体环境为体积分数3%左右的CO2和体积分数16%左右的O2,保持了软枣猕猴桃较好品质的机制,通过诱导果实的苯丙烷及抗氧化代谢实现。 相似文献
14.
15.
Petra E. de Jongh Tamara M. Eggenhuisen 《Advanced materials (Deerfield Beach, Fla.)》2013,25(46):6672-6690
The rapidly expanding toolbox for design and preparation is a major driving force for the advances in nanomaterials science and technology. Melt infiltration originates from the field of ceramic nanomaterials and is based on the infiltration of porous matrices with the melt of an active phase or precursor. In recent years, it has become a technique for the preparation of advanced materials: nanocomposites, pore‐confined nanoparticles, ordered mesoporous and nanostructured materials. Although certain restrictions apply, mostly related to the melting behavior of the infiltrate and its interaction with the matrix, this review illustrates that it is applicable to a wide range of materials, including metals, polymers, ceramics, and metal hydrides and oxides. Melt infiltration provides an alternative to classical gas‐phase and solution‐based preparation methods, facilitating in several cases extended control over the nanostructure of the materials. This review starts with a concise discussion on the physical and chemical principles for melt infiltration, and the practical aspects. In the second part of this contribution, specific examples are discussed of nanostructured functional materials with applications in energy storage and conversion, catalysis, and as optical and structural materials and emerging materials with interesting new physical and chemical properties. Melt infiltration is a useful preparation route for material scientists from different fields, and we hope this review may inspire the search and discovery of novel nanostructured materials. 相似文献
16.
17.
In recent years, solar cell technology has advanced significantly and is nearing commercial viability. Practical solar cells
that are capable of converting the solar radiation directly into electricity are now available. It is, however, imperative
to couple them with appropriate power storage systems. This article is a brief review of the current status of electrochemical
power systems such as storage batteries and fuel-electrolysis cell hybrids which could be successfully utilized to this end.
Communication No. 218. 相似文献
18.
Designing Heterogeneous 1D Nanostructure Arrays Based on AAO Templates for Energy Applications 下载免费PDF全文
Liaoyong Wen Zhijie Wang Yan Mi Rui Xu Shu‐Hong Yu Yong Lei 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(28):3408-3428
In order to fulfill the multiple requirements for energy production, storage, and utilization in the future, the conventional planar configuration of current energy conversion/storage devices has to be reformed, since technological evolution has promoted the efficiency of the corresponding devices to be close to the theoretical values. One promising strategy is to construct multifunctional 1D nanostructure arrays to replace their planar counterparts for device fabrication, ascribing to the significant superiorities of such 1D nanostructure arrays. In the last three decades, technologies based on anodic aluminium oxide (AAO) templates have turned out to be valuable meaning for the realization of 1D nanostructures and have attracted tremendous interest. In this review, recent progress in energy‐related devices equipped with heterogeneous 1D nanostructure arrays that fabricated through the assistance of AAO templates is highlighted. Particular emphasis is given on how to develop efficient devices via optimizing the componential and morphological parameters of the 1D nanostructure arrays. Finally, aspects relevant to the further improvement of device performance are discussed. 相似文献
19.