title: Electrochemical incorporation of hemin in a ZnO-PPy nanocomposite on a Pt electrode as NO(x) sensor.
abstract: An electrochemical NO(x) sensor was fabricated based on the incorporation of hemin on a ZnO-PPy nanocomposite modified Pt electrode. Scanning electron microscopy, energy dispersive X-ray analysis and cyclic voltammetry were used to confirm the successful stepwise assembly procedure for the sensor. The electrocatalytical behavior of the sensor was investigated by cyclic voltammetry. The hemin-ZnO-PPy-Pt electrode exhibited characteristic hemin reversible redox peaks at 0.035 V and -0.11 V vs. Ag/AgCl respectively. The hemin-ZnO-PPy-Pt electrode exhibited 3-fold enhanced electrocatalytic activity towards NO(x) compared to the hemin-PPy-Pt electrode. The electrocatalytic response of the sensor was proportional to the NO(x) concentration in the range of 0.8 to 2000 μM (r(2) = 0.9974) with a sensitivity of 0.04 μA μM(-1) cm(-2) and detection limit of 0.8 μM for the hemin-ZnO-PPy-Pt electrode. The low detection limit, wide linear range and enhanced sensitivity of the present sensor make it valuable for potential applications. In addition, this sensor exhibited good reproducibility and stability.
authors.affiliation: Department of Physics, VHNSN College, Virudhunagar-626 001, India. mms_prakash@yahoo.co.in
authors.forename: Subash
authors.initials: S
authors.lastname: Prakash
authors.forename: Seenivasan
authors.initials: S
authors.lastname: Rajesh
authors.forename: Sarkkarai Raja
authors.initials: SR
authors.lastname: Singh
authors.forename: Chandran
authors.initials: C
authors.lastname: Karunakaran
authors.forename: Veerapandy
authors.initials: V
authors.lastname: Vasu
mesh_terms: D002623:Chemistry Techniques, Analytical / Q000295:instrumentation*; D004563:Electrochemistry; D004566:Electrodes; D006427:Hemin / Q000737:chemistry*; D053761:Nanocomposites / Q000737:chemistry*; D009589:Nitrogen Oxides / Q000032:analysis* / Q000737:chemistry; D010984:Platinum / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D011758:Pyrroles / Q000737:chemistry*; D015203:Reproducibility of Results; D013997:Time Factors; D015034:Zinc Oxide / Q000737:chemistry*
chemical_list: D009589:Nitrogen Oxides; D011108:Polymers; D011758:Pyrroles; C067635:polypyrrole; D010984:Platinum; D006427:Hemin; D015034:Zinc Oxide