Evaluating the performance of polypyrrole nanowires on the electrochemical sensing of ammonia in solution

Abstract

a b s t r a c tThis work encompasses the direct electrodeposition of polypyrrole nanowires onto Au substrates using different electrochemical techniques: normal pulse voltammetry (NPV) and constant potential method with the aim in applying these films for the first time in ammonia sensing in solution. The performance of these nanowire-based sensors are compared and evaluated in terms of: film morphology (analyzed with scanning electron microscopy); their sensitivity towards ammonia; electrochemical and contact angle measurements. For nanowires prepared by NPV, the sensitivity towards ammonia increases with increasing amount of electrodeposited polypyrrole, as expected due to the role of polypyrrole as electrochemical transducer for ammonia oxidation. On the other hand, nanowires prepared potentiostatically displayed an unexpected opposite behavior, attributed to the lower conductivity of longer polypyrrole nanowires obtained through this technique. These results evidenced that the analytical and physico-chemical features of nanostructured sensors can differ greatly from those of their conventional bulky analogous.

Single-step synthesis of polypyrrole nanowires by cathodic electropolymerization

“…Recently, electrochemical methods using perchlorate (ClO 4 )-based chemical additives have also been studied as an alternative way to synthesize the polypyrrole nanowires without hard or so templates. [24][25][26] These approaches provide not only a simple and facile technique for depositing polypyrrole nanowires on a substrate but also an easy way to control the structural characteristics and electrical conductivity by simply changing the electrolysis composition.…”

Fabrication of Hollow Nanocones Membrane with an Extraordinary Surface Area as CO2 Sucker

“…However, several limitations included the high cost, the risk of damage during the hard templates’ removal process, and the complex preparation process. Thus, more effort has been given to the template-free preparation of micro-/nanostructured hPPy film-modified substrates based on the electrochemical technique during the last decade [ 45 , 46 , 47 , 48 , 49 , 50 ]. The electrochemical polymerization has various advantages, such as a one-step preparation technique, no need to remove the template after the polymerization, and the morphology/properties of the prepared membrane being easy to control [ 51 , 52 , 53 ].…”

Facile preparation of functional and hybrid coatings by precipitations of polypyrrole and lysozyme via co‐assembly process

“…Polypyrrole is one of the most outstanding conductive polymers, which has been widely studied due to the advantages of easy preparation, low redox potential, good stability, and conductivity 15,16 . Owing to the excellent conductivity and non‐toxicity, chemical stability, and easy synthesis, and so on, it holds a widely application in functional material devices, 17 biomedical, 18,19 electrode materials, 20,21 sensors and so on 22,23 . During polymerization from the pyrrole (Py) monomers, PPy nanoparticles will gather chaotically to form aggregation via oxidation 2 .…”