Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education, China), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, PR China.
Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education, China), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, PR China.
J Colloid Interface Sci. 2021 May 15;590:365-374. doi: 10.1016/j.jcis.2021.01.063. Epub 2021 Jan 27.
Present work reports preparation of colloidal single/few layer TiCT MXene flakes using minimally intensive layer delamination (MILD) method for rapid electroanalytical screening of carbamate pesticides. Lithium fluoride salt and hydrochloric acid (7.5 M LiF/9M HCl) was used to produce in-situ generated HF as etchant to remove Al successfully from TiAlC MAX phase. Unlike the clay method (5 M LiF/6M HCl), this methodology simplified TiCT synthesis protocol resulting in Li ions intercalated TiCT which was delaminated without further sonication. The delaminated TiCT flakes were found to be single/few layered sheets with mostly -OH and -O terminated surface groups. The characteristic 002 peak observed in X-ray diffraction (XRD) at 2θ = 6.4° with interplaner distance of 1.1137 nm suggested broadening of the peak attributed to the presence of Li ions between TiCT flakes. Delaminated TiCT flakes were utilized as working electrode which demonstrated simultaneous and selective detection of carbamate pesticides methiocarb and diethofencarb by voltammetry. The oxidation peaks of the two pesticides were well separated by a potential difference of 0.35 V in 0.5 M HSO and DPV detection limits were calculated as 0.19 μg mL and 0.46 μg mL for methiocarb and diethofencarb respectively. TiCT flakes as electrochemical sensor exhibited long term stability and acceptable recoveries in real sample for environmental applications.
本工作报道了使用最小程度层剥离（MILD）方法制备胶体单层/少层 TiCT MXene 薄片，用于快速电分析筛选氨基甲酸酯类农药。使用氟化锂盐和盐酸（7.5 M LiF/9 M HCl）原位生成 HF 作为蚀刻剂，成功地从 TiAlC MAX 相中去除 Al。与粘土法（5 M LiF/6 M HCl）不同，该方法简化了 TiCT 的合成方案，导致锂离子插层 TiCT 无需进一步超声处理即可剥离。剥离的 TiCT 薄片被发现为单层/少层片状，表面主要带有 -OH 和 -O 端基。在 X 射线衍射（XRD）中观察到的 002 峰在 2θ = 6.4°，层间距离为 1.1137nm，表明由于 TiCT 薄片之间存在锂离子，峰宽变宽。剥离的 TiCT 薄片被用作工作电极，通过伏安法同时选择性地检测氨基甲酸酯类农药甲硫威和二乙基硫代氨基甲酸酯。两种农药的氧化峰在 0.5 M HSO 中的电位差为 0.35 V 时得到很好的分离，甲硫威和二乙基硫代氨基甲酸酯的 DPV 检测限分别计算为 0.19μgmL 和 0.46μgmL。TiCT 薄片作为电化学传感器在环境应用中具有长期稳定性和可接受的实际样品回收率。
