A three-dimensional hierarchical network of bismuth nanoparticles decorated graphene-carbon nanotubes nanocomposite (Bi NPs@Gr-CNTs) was synthesized and employed for electrocatalytic detection of mercury (Hg (II)). The electrocatalyst was characterized via scanning electron microscopy, transmission electron microscopy, Energy-dispersive X-ray spectroscopy, X-ray diffraction, FT-IR, electrochemical impedance spectroscopy, and cyclic voltammetry. The electrocatalytic activity of Bi NPs@Gr-CNTs modified screen-printed carbon electrode (SPCE) toward Hg (II) was studied using cyclic voltammetry, and differential pulse voltammetry. The Bi NPs@Gr-CNTs/SPCE exhibited excellent electrocatalytic ability to Hg (II) in comparison to control electrodes. Under optimized conditions, Bi NPs@Gr-CNTs/SPCE exhibits excellent Hg (II) sensing attributes in the range of 1.0 nM–217.4 µM with 0.2 nM of detection limit. The electrode was specific for Hg (II) in presence of other metal ions ascribe excellent selectivity. Practicality of the method was demonstrated in tap water, fish oil tablet, human serum, and urine samples (spiked method), which presented acceptable recoveries.

合成了由铋纳米粒子修饰的石墨烯-碳纳米管纳米复合物（Bi NPs @ Gr-CNTs）的三维层次网络，并将其用于电催化检测汞（Hg（II））。通过扫描电子显微镜，透射电子显微镜，能量色散X射线光谱，X射线衍射，FT-IR，电化学阻抗光谱和循环伏安法对电催化剂进行表征。采用循环伏安法和微分脉冲伏安法研究了Bi NPs @ Gr-CNTs修饰的丝网印刷碳电极（SPCE）对汞的电催化活性。与控制电极相比，Bi NPs @ Gr-CNTs / SPCE对Hg（II）表现出优异的电催化能力。在优化条件下，Bi NPs @ Gr-CNTs / SPCE在1.0 nM–217.4 µM的范围内具有出色的Hg（II）感测属性，检测限为0.2 nM。在存在其他金属离子的情况下，该电极对Hg（II）具有特异性，因此具有出色的选择性。该方法的实用性在自来水，鱼油片，人血清和尿液样品（加标方法）中得到了证明，其回收率令人满意。