The fabrication of the schottky junction diode using aligned polypyrrole nanofibers for the broad range detection of M-dihydroxybenzene

Aligned p-type polypyrrole (PPy) nanofibers (NFs) thin film is grown on n-type silicon (100) substrate by an electrochemical technique to fabricate Schottky junction diode for the efficient detection of mdihydroxybenzene chemical. The highly dense and well aligned PPy NFs with the average diameter (~150-200 nm) are grown on n-type Si substrate. The formation of aligned PPy NFs is confirmed by elucidating the structural, compositional and the optical properties. The electrochemical behavior of the fabricated Pt/p-aligned PPy NFs/n-silicon Schottky junction diode is evaluated by cyclovoltametry (CV) and current (I)-voltage (V) measurements with the variation of m-dihydroxybenzene concentration in the phosphate buffer solution (PBS). The fabricated Pt/paligned PPy NFs/n-silicon Schottky junction diode exhibits the rectifying behavior of I-V curve with the addition of m-dihydroxybenzene chemical, while a weak rectifying I-V behavior is observed without m-dihydroxybenzene chemical. This nonlinear I-V behavior suggests the formation of Schottky barrier at the interface of Pt layer and aligned PPy NFs/n-silicon thin film layer. By analyzing the I-V characteristics, the fabricated Pt/paligned PPy NFs/n-silicon Schottky junction diode displays reasonably high sensitivity ~23.67 µAmM^-1cm^-2, good detection limit of ~1.51 mM with correlation coefficient (R) of ~0.9966 and short response time (10 s).