【作者】 谢贝贝； 任晓丹； 李亚； 尚卷卷； 魏鑫； 张人杰；

【Author】 Beibei Xie;Xiaodan Ren;Ya Li;Juanjuan Shang;Xin Wei;Renjie Zhang;Key Laboratory of Colloid and Interface Chemistry of the Ministry of Education of the P.R.China,Shandong University;

【机构】 胶体与界面化学教育部重点实验室(山东大学)；

【摘要】 石墨烯气凝胶(graphene aerogel,GA)的物化性质与其内部孔径大小有关[1]。氧化石墨烯(graphene oxide,GO)的两亲性、导电率和透光性与其尺寸和氧化程度紧密相关。[2]有必要通过GO大小调控GA的孔径大小及性能。目前尚无见相关报道。本文提出了一个制备和应用不同大小和氧化程度氧化石墨烯纳米片(GONSs,graphene oxide nanosheets)的方法,并以GONSs与多巴胺(dopamine,DA)作为前驱体,调节具有优异机械性能和电催化生物传感活性的氮掺杂石墨烯气凝胶(nitrogen-doped graphene aerogel,NGA)孔径大小的方法。不同大小和氧化程度的GONSs(Figure 1a-c)由改进的Hummers法与超声[3]结合获得。没有超声和超声处理4、8 h的GONSs分别被标记为GONSs-0、GONSs-4、GONSs-8。GONSs的尺寸越小、氧化程度越高,相应的NGA氮含量越高、比表面积越大、孔径和孔体积越小(Figure 1d-f)、电催化活性越高。可同步检测抗坏血酸(AA),DA和尿酸(UA)混合溶液中的单一组分(Figure 1g)。DA既作为N源,又通过与石墨烯的交联增加了NGA的机械稳定性(Figure 1h)。本工作可为石墨烯材料的结构调控及其在高灵敏度生物检测技术方面的应用提供指导。更多还原

【Abstract】 The inner pore size of graphene aerogel(GA) correlates with its physicochemical properties.The amphiphilicity,conductivity and transmittance of graphene oxide nanosheets(GONSs) closely depend on the size and oxidation degree of GONSs.It is necessary to study the modulation of the pore size and function of GA by changing the size of GONSs,which has so far not been reported.In this work,a strategy of porosity modulation of a nitrogen-doped graphene aerogel(NGA) showing excellent mechanical stability and electrocatalytic biosensing activity is proposed by using different size and oxidization degree of GONSs together with the dopamine(DA) as precursors.These GONSs were obtained by varying the sonication time for GONSs synthesized by an improved Hummers method.The GONSs subjected to ultrasonication for 0,4,8 h are named as GONSs-0,GONSs-4,GONSs-8,respectively.The smaller the GONSs are,and higher oxidization degree and the higher nitrogen content NGA has,the larger the specific surface area is,the smaller pore size and pore volume are,the better the electrocatalytic activity.The NGA with DA and the smallest GONSs as precursors can simultaneously determine the concentration of ascorbic acid(AA),DA,and uric acid(UA) in their ternary mixture.Besides as the nitrogen source,DA helps to stabilize the NGA by crosslinking the graphene nanosheets.The strategy in this work provides guidance to modulate the structure and bioassay activity of graphene materials.更多还原