posted on 2019-10-08, 13:03authored byWei Zhao, Haoyu Yang, Sheng Xu, Xiaojie Li, Wei Wei, Xiaoya Liu
A high-performance
nitrite sensor based on a unique “olive-structured”
electroactive copolymer/multiwalled carbon nanotube (MWCNT) nanocomposite
is demonstrated for nitrite monitoring in the environmental system.
An electroactive, amphiphilic copolymer was designed to noncovalently
functionalize MWCNTs. The copolymer and MWCNTs were co-assembled to
form a water-dispersed copolymer/MWCNT nanocomposite with an olivelike
appearance. A simple drop-casting method was utilized to fabricate
the nitrite sensor. After electrochemical postpolymerization of the
copolymer, an interpenetrating electroactive network was established:
a macro entanglement of MWCNTs and a molecular-level conjugated structure
of polycarbazole. Such an electroactive internetwork with different
scales is expected to enhance the electrochemical signal from the
molecular level to the microscale. The electrochemical properties
of the sensor indicated that electropolymerized nanocomposites exhibited
an improved electrocatalytic activity for nitrite detection with a
linear response range of 0.01–25 μM. The excellent sensing
performance demonstrated that it was an effective candidate for practical
monitoring of nitrite in various real samples.