A carbon fiber cloth (CFC)‐supported Au nanodendrite (AuND@CFC) sensor was used to simultaneously measure the concentrations of Pb(II), Cu(II) and Hg(II) in real water samples. The sensor had a large electrochemically active surface area due to the hierarchical nanodendrite structure and the formation of the nanodendrite structure on the CFC was accomplished in just 5 minutes by single‐step electrodeposition. After the optimization of important experimental conditions, such as pH and pre‐concentration time, the achieved limit of detections (LODs) in the measurements of Pb(II), Cu(II) and Hg(II) were 0.15, 0.07, and 0.13 ppb, respectively, which were superior and comparable to those reported in previous studies. The electrochemical responses of each analyte (concentration: 2.0 ppb) were not influenced when the concentrations of interferants (Cr(IV), Ni(II), Mn(II), Zn(II), Al(III), Ca(II) and Mg(II)) were even 500‐fold greater (1.0 ppm); while only the signal of Cu(II) decreased when the Ni(II) concentration were 4.0 ppm (2000‐fold larger). When eight separately prepared AuND@CFC sensors were used to measure the samples, the relative standard deviations (RSDs) of the peak intensities of these metals were lower than 5.0 %, thereby indicating the superior sensor‐to‐sensor reproducibility. When real river and lake water samples were analyzed, the determined concentrations were similar to those measured with ICP‐MS and the recoveries ranged from 93.2 %–118.7 %. Overall, the proposed sensor is versatile enough to be incorporated into a portable analytical system for on‐site detection of Pb(II), Cu(II) and Hg(II) in real field samples.

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In this study, bismuth nanodendrites (BiNDs) were fabricated on glassy carbon electrode by chronopotentiometric method. The hierarchical structure and high population matrix of BiNDs provides high surface active area to enhance the electrochemical signals of measured Cd2+ and Pb2+ ions. The developed bismuth nanodendritic structure was well‐observed and characterzied by scanning electron microscopy (SEM). Electrochemical behaviours of developed BiNDs electrodes were studied by the cyclic voltammetric (CV) method. The fabrication conditions for BiNDs such as the applied current and deposition time were optimized as ‐10 mA and 90 s, respectively. Under this optimized condition, the highest peaks of Cd2+ and Pb2+ ions at concentration of 20 ppb were obtained. The Cd2+ and Pb2+ signals acquired by BiNDs are almost three times greater than that measured by the Bi film electrode.

Due to their electrochemical and economical characteristics, pencil leads can be used as electrodes for electrochemical analysis. These graphite-based electrodes are recognized by their low-cost and commercial availability. This paper presents the synthesis of gold nanodendrite network porous structure on pencil lead and its application in recording signals of Hg(II) in water environment. Influences of deposition time (t dep ) used to fabricate Au nanodendrite structure on electrodes surface, sensor electrochemical behaviors and voltammetric signal of Hg(II) have been studied.The obtained results open a possibility to employ this simple, eco-friendly material in developing electrochemical sensor, which can be implemented for heavy metal detection.