Abstract:
This study centers on the development and characterization of an innovative electrochemical sensing probe composed of a sensing mesoporous functional sol-gel coating integrated onto a glassy carbon electrode (sol-gel/GCE) for the detection of NH3 and/or NH4+ in water. The main interest for integrating a functional sol-gel coating onto a GCE is to increase the selective and sensing properties of the GCE probe towards NH3 and/or NH4+ ions. The structure and surface morphology of the newly developed sol-gel/GCE probe were characterized employing scanning electron microscopy (SEM), atomic force microscopy (AFM), dynamic light scattering (DLS), and Fourier-transform infrared (FTIR), while the electrochemical sensing properties were evaluated by Berthelot\'s reaction, cyclic voltammetry (CV), and adsorptive square wave-anodic striping voltammetry (Ads SW-ASV). It is shown that the newly developed sol-gel coating is homogeneously deposited on the GCE with a sub-micron and uniform thickness close to 630 nm and a surface roughness of 25 nm. The sensing testing of the sol-gel/GCE probe showed limits of detection and limits of quantitation of 1.7 and 5.56 nM of NH4+, respectively, as well as a probe sensitivity of 5.74 × 10-1 μA/μM cm-2. The developed probe was fruitfully validated for the selective detection of NH3/NH4+ in fresh and sea water samples. Computed Student texp (0.45-1.25) and Fexp (1.69-1.78) (n = 5) tests were less than the theoretical ttab (2.78) and Ftab (6.39) at 95% probability.
摘要:
这项研究的重点是开发和表征创新的电化学传感探针,该探针由集成在玻碳电极(溶胶-凝胶/GCE)上的传感介孔功能溶胶-凝胶涂层组成,用于检测水中的NH3和/或NH4。将功能性溶胶-凝胶涂层整合到GCE上的主要兴趣是增加GCE探针对NH3和/或NH4+离子的选择性和感测性质。采用扫描电子显微镜(SEM)表征了新开发的溶胶-凝胶/GCE探针的结构和表面形貌,原子力显微镜(AFM),动态光散射(DLS),和傅里叶变换红外(FTIR),而电化学传感性能是通过Berthelot反应来评估的,循环伏安法(CV),和吸附方波-阳极剥离伏安法(AdsSW-ASV)。表明,新开发的溶胶-凝胶涂层均匀地沉积在GCE上,其亚微米且均匀的厚度接近630nm,表面粗糙度为25nm。sol-gel/GCE探针的传感测试显示检测限和定量限为1.7和5.56nM的NH4+,分别,以及5.74×10-1μA/μMcm-2的探针灵敏度。成功验证了所开发的探针对淡水和海水样品中NH3/NH4的选择性检测。计算的学生texp(0.45-1.25)和Fexp(1.69-1.78)(n=5)测试在95%概率下小于理论ttab(2.78)和Ftab(6.39)。