A highly sensitive sensing strategy based on 2D bimetallic MOFs and multi-walled carbon nanotubes

Developing new and high-performance sensitive materials is of great importance for electrochemical sensors. In view of the large specific surface area and excellent electrocatalytic activity of bimetallic 2D MOFs, outstanding conductivity of multi-walled carbon nanotubes (MWCNTs), NiCo bimetallic 2D MOFs was fabricated on MWCNTs via an in-situ growth method at room temperature. The composition, morphology, structure, and electrochemical properties of serious mono/bimetallic 2D MOFs/MWCNTs composite were compared, revealing the combination of bimetallic 2D MOFs and MWCNTs could effectively improve the specific surface area, electrochemical active area, electron transfer and electrocatalytic ability, which matched well with our design intent. Benefiting from these, the as-synthesized bimetallic 2D MOFs/MWCNTs hybrids showed superior electrochemical activity toward the oxidation and sensing of target molecules that were closely related to people's lives and health (e.g. DA, AC, and BPA). Their detection limits were as low as 5.1, 14.7 and 169 nM (S/N=3), respectively. A trusted sensor platform for DA, AC, and BPA determination in real samples was then successfully developed, and showed satisfied recovery. This work will create a new idea for the development of highly sensitive and highly selective electrochemical sensing materials, and provide a new method for the rapid detection of life and health related molecules.