Polyvinyl alcohol (PVA)/chitosan (CS) nanofibers modified with carbon nanotubes (CNT) and silver (Ag) particles are electrospun onto a graphite plate (GP) substrate to form the PVA-CS-CNT-Ag/GP electrode for electrochemical sensor application. Microstructure characterization demonstrates that PVA-CS nanofibers exhibit a loose and porous network structure, significantly improving the effective reaction surface area. Electrochemical measurements show the PVA-CS-CNT-Ag/GP electrode exhibits the limit of detection of 23.2 μM, the linear range of 65–176,460 μM and the sensitivity of 3.3945 μA cm−2 mM−1. Anti-interference test results show that the sensor has high selectivity towards H2O2. Stability test results indicate that the sensor exhibits good stability, as evidenced by the response current of 83.94 % after a period of 30 days. Simulation calculations indicate that PVA-CS-CNT-Ag exhibits lower interfacial energy (−2.3293 eV) compared to PVA-CS-CNT (−0.3674 eV) and PVA-CS-Ag (−0.7646 eV), smaller band gap (0.318 eV) compared to PVA-CS (3.640 eV), higher density of states at Fermi level (14.7332 electrons/eV) than others. Experimental measurements and simulation calculations indicate that PVA-CS-CNT-Ag electrospun nanofibers exhibit promising potential as an electroactive material for the electrochemical detection of H2O2.
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