Electrodes for paracetamol sensing modified with bismuth oxide and oxynitrate heterostructures: An experimental and computational study

In this work, novel platforms for paracetamol sensing were developed by the deposition of Bi2O3, Bi5O7NO3 and their heterostructures onto screen-printed carbon-paste electrodes. An easy and scalable solid state synthesis route was employed, and by setting the calcination temperatures at 500◦C and 525◦C we induced the formation of heterostructures of Bi2O3 and Bi5O7NO3. Cyclic voltammetry measurements highlighted that the heterostructure produced at 500◦C provided a significant enhancement in performance compared to the monophases of Bi2O and Bi5O7NO3, respectively. That heterostructure showed a mean peak-to-peak separation Ep of 411 mV and a sensitivity increment of up to 70% compared to bare electrodes. A computational study was also performed in order to evaluate the geometrical and kinetic parameters of representative clusters of bismuth oxide and subnitrate when they interact with paracetamol.