In situ construction of hollow carbon spheres with N, Co, and Fe co-doping as electrochemical sensors for simultaneous determination of dihydroxybenzene isomers
In situ construction of hollow carbon spheres with N, Co, and Fe co-doping as electrochemical sensors for simultaneous determination of dihydroxybenzene isomers
复制标题
原位构建 N、Co、Fe 共掺杂空心碳球作为同时测定二羟基苯异构体的电化学传感器
作者：
Yang Hui;Li Shunxing;Yu Huiwu;Zheng Fengying;Lin Luxiu;Chen Jie;Li Yuehai;Lin Ye
活性位点/中心的控制在设计具有特殊性能的新型电极材料和实现高性能传感器中起着重要作用。本研究采用简单模板法（以SiO2为模板）和低成本的原位自聚合、自吸附/还原和碳化策略，合成了层厚为30 nm的三维（3D）独立多掺杂空心碳球（N - Co - Fe - hcs），其中含有杂原子N和过渡金属（Co和Fe）的多个活性位点。此外，采用相同的方法和前驱体，采用不同的掺杂元素，用该方法制备了一系列同族中空碳球复合材料（N-HCS、N-Co-HCS和N-Fe-HCS）。这些差异导致空心碳球的活性位点/中心不同，并提高了二羟基苯异构体的电催化活性。此外，N-Co-Fe-HCS作为电化学传感器对儿茶酚（CC）和对苯二酚（HQ）具有良好的同时定性和定量测定性能。CC的检出限为75 μmol L−1，线性范围为0.5 ~ 500 μmol L−1；HQ的检出限为80 μmol L−1，线性范围为0.5 ~ 1500 μmol L−1。河水中同时存在的成分对CC和HQ的检测没有干扰。这些结果表明，通过在电极材料中原位掺杂多元素以获得多活性位点，可以构建高性能的电化学传感器。
Control of the active sites/centers plays an important role in the design of novel electrode materials with unusual properties and achievement of sensors with high performance. In this study, three-dimensional (3D) freestanding multi-doped hollow carbon spheres (N–Co–Fe–HCS) with a layer thickness of 30 nm, which contained multiple active sites of the heteroatom N and transition metals (Co and Fe), were synthesized via a simple template method (with SiO2 as the template) and cost-efficient in situ self-polymerization, self-adsorption/reduction and carbonization strategies. Moreover, a series of hollow carbon sphere composites of the same family (N–HCS, N–Co–HCS and N–Fe–HCS) were prepared by this sensible process using the same method and precursors but different doping elements. These differences lead to different active sites/centers from hollow carbon spheres and improved electrocatalytic activities for dihydroxybenzene isomers. Furthermore, N–Co–Fe–HCS as an electrochemical sensor exhibited excellent simultaneous qualitative and quantitative determination performance for catechol (CC) and hydroquinone (HQ). The detection limit and the linear range were 75 nmol L−1 and 0.5–500 μmol L−1 for CC and 80 nmol L−1 and 0.5–1500 μmol L−1 for HQ, respectively. The interference from the components coexisting in river water on the detection of CC and HQ was not observed. These results indicate that high-performance electrochemical sensors can be constructed by in situ multi-element doping into electrode materials to achieve multi-active sites.