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1.
成功制备了氧化石墨烯(GO)和SiO2/CMC的复合膜(GO-SiO2-CMC),将其修饰固体玻碳电极后构成电化学传感器用于维生素B6(VB6)的痕量检测。利用扫描电子显微镜和电化学技术分别研究该复合膜的微观形貌和电化学性能。结果表明,修饰电极对VB6表现出较强的电化学敏感性,对VB6的检测具有较高的灵敏度(31.5μAmM-1cm-2)、较低的检测限(10-7M)和较小的表面阻抗值(252Ω)。GO-SiO2-CMC对VB6的检测,提供了一种新型的简单高效的VB6检测技术。  相似文献   

2.
石墨烯具有独特的纳米结构和一系列极具吸引力的特性,成为新型纳米复合材料的理想载体,如纳米复合材料分散的基体.提出了一种以石墨,苯胺,四氯化锡为原料制备石墨烯/二氧化锡/聚苯胺的新方法.通过X-射线衍射,红外光谱,透射电子显微镜,扫描电子显微镜以及紫外-可见光谱对合成的材料进行表征.结果表明:二氧化锡纳米粒子原位吸附在石墨烯的表面,有效地避免了石墨烯片的堆叠,聚苯胺加入后可大大提高二氧化锡的电化学性质.  相似文献   

3.
石墨烯量子点是石墨烯中一种新型的碳基零维纳米材料,除了具备石墨烯本身的物理化学性质之外,同时拥有良好的生物相容性、稳定性、低毒性、光致发光等特性。报导了一种以多壁碳纳米管(MWCNTs)为碳源,通过改良的Hummers法氧化剥离制备石墨烯量子点(GQDs)的简单方法,所得到的GQDs样品具有很强的光电子性能。作为一种有效的增效剂,通过简单的湿浸渍法和肼还原法成功的合成了P25-R-GOQDs-N纳米复合材料。在可见光照射下,对有机染料罗丹明B(Rh B)进行光催化降解实验,相比于P25(商业化Ti O2),P25-R-GOQDs-N样品显示出更高的光催化活性,表明石墨烯量子点起到了关键作用。  相似文献   

4.
Coals consist of some molecules trapped within an organic matrix from which some organic compounds can be extracted by solvents. The Soxhlet technique has been widely used for extracting organic compounds. Microwave heating methods may be successfully applied in the field of coal science. Acetone extraction yields and the chemical composition of the extract were inves-tigated using a typical Chinese coal, Shenfu coal, with microwave-assisted extraction. The acetone extract and residue were ana-lyzed by GC/MS and carbon-13 nuclear magnetic resonance spectroscopy respectively. The carbon spectra were converted into several numerical parameters, fa, Ha, Xb, which indicate the difference in macromolecular structure between Shenfu coal and its residue. Furthermore, a hybrid genetic algorithm was employed using these parameters to approximate a coal macromolecule by assembling the structural fragments or functional groups into a large and complicated structure.  相似文献   

5.
A new method for the determination of DNA was developed with azocarmine G(AG) in the presence of cetyltrimethylammonium bromide(CTAB) by the resonance light scattering (RLS) technique. The synthetic samples were determined with satisfactory results, and the reaction mechanism was also studied. The results show that under the optimum conditions, the weak RLS signal of AG can be enhanced by DNA, which results from the formation of a new ternary complex AG-CTAB-DNA with large size. Moreover, the enhanced RLS intensity at 552 nm is directly proportional to the concentration of DNA in the range of 0 - 1.0 μg/mL for fish sperm DNA (fsDNA) and 0 - 1.5μg/mL for calf thymus DNA (ctDNA). Based on this, a new assay of DNA can be established. The detection limits (3σ) are 2. 1 ng/mL for fsDNA and 2.2 ng/mL for ctDNA, respectively.  相似文献   

6.
为了研发高性能的锂离子电池负极材料,采用水热法合成了Bi2S3-MoS2/石墨烯复合材料,利用X-射线衍射(XRD)、扫描电镜(SEM)、高分辨透射电镜(HRTEM)、热重分析(TGA)和X-射线光电子能谱(XPS)对复合材料进行表征,讨论复合材料的微观结构对电化学储锂性能的影响. 特别是,当Bi与Mo的物质的量之比为1∶4时,Bi2S3-MoS2/石墨烯的电化学储锂可逆比容量可以达到1 140 mA·h/g,并具有稳定的循环性能. 当充放电电流密度为1 000 mA/g时,其高倍率特性为886 mA·h/g. Bi2S3-MoS2/石墨烯复合材料优异的电化学储锂性能主要由于MoS2具有更少的层数和较多的边缘以及Bi2S3纳米粒子具有更均匀的粒径,并能很好地分散在石墨烯表面,增强了复合材料容纳锂离子的能力,改善了储锂电极过程的动力学性能.  相似文献   

7.
Functionalized graphene nano-platelets(FGN) were obtained via treating graphene nanoplatelets(GN) with HNO_3, and served as adsorbent for the removal of Pb~(2+) from solutions. We investigated the FGN adsorption capacity for Pb~(2+) at different initial concentrations, varying pH, contact time and temperature. The characterization results of scanning electron microscopy(SEM), thermal analysis(TG/DTG), Fourier transform infrared spectroscopy(FT-IR) and Brunauer-Emmett-Teller(BET) method indicated that FGN layers were thin and possess large specific area with oxygen-containing functional groups grafted onto their surface. Meanwhile, the determined equilibrium adsorption capacity of FGN for Pb~(2+) was 57.765 mg/g and adsorption isotherms well confirmed to Langmuir isotherms models. The results reveals that the FGN has better effect of water treatment.  相似文献   

8.
以钛酸正丁酯为钛源,采用一种简单的原位水解技术制备了石墨烯/二氧化钛复合光催化剂.通过XRD、SEM、TEM、Raman、PL和UV-vis光谱仪等分析手段对产物进行了表征,并测试了该复合光催化剂在可见光区对染料罗丹明B的光催化降解性能.实验结果表明:制备的复合光催化剂主晶相为锐钛矿型二氧化钛,石墨烯表面富集的二氧化钛颗粒尺寸约为10-20nm左右,均匀弥散、形成一层致密的氧化钛膜层.样品降解罗丹明B测试结果表明,石墨烯与二氧化钛的复合,一方面使得二氧化钛光催化剂在可见光区的吸收大大增强,另外,石墨烯的存在能够促进二氧化钛半导体中电子和空穴的有效分离,并且在一定程度上提高了污染物在半导体表面的富集效率,从而使石墨烯/二氧化钛复合光催化剂对降解罗丹明B表现出良好的光催化活性.  相似文献   

9.
为了制备高效、低成本的析氢反应电催化剂,采用一步水热法制备镍掺杂二硫化钼/石墨烯复合材料(Nix-MoS2/G,x=0.03,0.05,0.10),并用X-射线衍射(XRD)、扫描电镜(SEM)、高分辨透射电镜(HRTEM)和X-射线光电子能谱(XPS)对其进行表征,讨论镍掺杂对复合材料的微观结构和电催化析氢性能的影响. 结果表明,与MoS2/G催化剂相比,镍掺杂的MoS2/G催化剂显示了更高的电催化析氢性能,尤其当水热反应体系中的Ni和Mo的摩尔比为1∶20时,制备的Ni0.05-MoS2/G显示了最强的电催化析氢性能,其塔菲尔斜率为50.8 mV/dec. 电催化活性的增强主要是由于少量镍的掺杂改变了复合催化剂的形貌,使MoS2纳米片更好地负载在石墨烯表面,暴露出更多的催化活性位点,同时镍掺杂提高了MoS2边缘活性位的固有催化活性.  相似文献   

10.
为了最大程度上保留石墨烯的晶格结构以提高其电导并简化过渡金属氧化物与石墨烯复合物的制备过程,通过氢电弧放电和简易的高温处理成功制备得到四氧化三锰/石墨烯纳米复合材料,并将其用作超级电容器的电极.通过XRD、Raman光谱和TEM对产物的形貌、结构及成分进行了表征.电化学测试结果表明,由该材料制得的超级电容器具有良好的电容性质、出色的电化学稳定性(循环3 000圈后大约保持96%)以及较低的等效串联电阻.同时,四氧化三锰的掺入可使其比电容提高到纯石墨烯电极的3倍.因此,此方法为制备以新型石墨烯复合过渡金属氧化物作为高性能超级电容器电极的研究提供了新思路.  相似文献   

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