Enhanced electrocatalytic activity in MOFs-derived 3D hollow NiCo-LDH nanocages decorated porous biochar for simultaneously ultra-sensitive electrochemical sensing of Cu2+ and Hg2

• Published in: Talanta (Oxford) Vol. 279; p. 126624
• Main Authors: Zou, Jiamin, Zou, Jin, Li, Li, Chen, Hui, Liu, Shuwu, Gao, Yansha, Huang, Xigen, Wang, Linyu, Lu, Limin
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.11.2024
• Subjects: Heavy metal ions; Hollow nanocages; Porous carbon; Simultaneous determination; Heavy metal ions; Simultaneous determination; Porous carbon; Hollow nanocages
• ISSN: 0039-9140; 1873-3573; 1873-3573
• DOI: 10.1016/j.talanta.2024.126624

Layered double hydroxides (LDHs) have attracted significant attention due to their compositional and structural flexibility. However, it is challenging but meaningful to design and fabricate hierarchical mixed-dimensional LDHs with synergistic effects to increase the electrical conductivity of LDHs and promote the intrinsic activity. Herein, 3D hollow NiCo-LDH nanocages decorated porous biochar (3D NiCo-LDH/PBC) has been synthesized by using ZIF-67 as precursor, which was utilized for constructing electrochemical sensing platform to realize simultaneous determination of Cu2+ and Hg2+. The 3D NiCo-LDH/PBC possessed the characteristics of hollow material and three-dimensional porous material, revealing a larger surface area, more exposed active sites, and faster electron transfer, which is beneficial to enhancing its electrochemical performance. Consequently, the developed sensor displayed good performance for simultaneously detecting Cu2+ and Hg2+ with ultra-low limit of detection (LOD) of 0.03 μg L−1 and 0.03 μg L−1, respectively. The proposed sensor also demonstrated excellent stability, repeatability and reproducibility. Furthermore, the sensor can be successfully used for the electrochemical analysis of Cu2+ and Hg2+ in lake water sample with satisfactory recovery, which is of great feasibility for practical application. The schematic diagram of the synthetic process of 3D NiCo-LDH/PBC based sensor and its application for simultaneous detection of Cu2+ and Hg2+. [Display omitted] •3D hollow NiCo-LDH nanocages decorated PBC was obtained from ZIF-67 template.•3D NiCo-LDH/PBC electrode was used for simultaneous detection of Cu2+ and Hg2+.•Hollow and porous structure favors the exposure of active sites for HMIs enrichment.•The limit of detections of Cu2+ and Hg2+ were down to 0.03 μg L−1 and 0.03 μg L−1.•The sensor was successfully applied to detect Cu2+ and Hg2+ in water samples.