Harnessing host–guest recognition and electron transfer in MXene–Fe₃O₄@Au–pillararene for enhanced 4-nitrophenol monitoring

Abstract

4-Nitrophenol (4-NP) is a major environmental pollutant, and its health risks call for efficient recognition methods. Here we developed a Ti₃C₂Tₓ MXene-supported cationic [2]biphenyl-extended pillar[6]arene-functionalized Fe₃O₄@Au platform for 4‑nitrophenol detection. It relies on host–guest recognition, fast electron transfer, and Fe²⁺/Fe³⁺ catalysis, achieving excellent electrocatalytic performance in environmental applications.