High-loading Bi-MOF nanoparticles anchored on biomass waste-derived carbon for sensitive non-enzymic nitrite sensing

A novel electrocatalyst based on loofah sponge-derived carbon-supported high-density Bi-MOF nanoparticles was designed and used for electrochemical nitrite detection. The use of conductive loofah sponge-derived carbon substrate to support Bi-MOF nanoparticles can not only accelerate electron transfer, thereby accelerating electrochemical reaction kinetics, but also effectively prevent the aggregation of MOF materials, promote the full exposure of MOF active sites, and improve electrochemical sensing performance. Benefitting from the synergy effect of conductive loofah sponge-derived carbon sustrate and highly loading Bi-MOF nanoparticles, the Bi-MOF-NPs/CLS electrode displayed high sensitivity of 190 µA cm^-2 mM^-1, a wide linear range from 5 µM to 1.4 mM, a low detection limit down to 0.5 µM (S/N = 3), and good anti-interference. These excellent electrochemical sensing properties make the developed electrode suitable for nitrite detection in environmental water samples.