Morphology controlled oxide nanostructures and their effect on biosensing capabilities and photocatalytic activity

Abstract

We report the fabrication of metal oxide nanostructure grown directly on the electrode surface by electrodeposition and thermal oxidation techniques. Chemical additives were used as morphology modifying agents to obtain morphology-controlled nanostructures. These nanostructures were used as platforms for biosensing applications as well the photoelectrochemical devices. The variation in morphology strongly influenced the performance of the electrodes. Nanomaterials have played an important role in such devices due to their unique properties. Zinc oxide (ZnO), cerium oxide (CeO₂), and copper oxide (CuO) are such promising materials and finds potential in various applications. Those nanostructures have attracted a lot of interest because of their many advantages, including high sensitivity, unique surface characteristics that influence adsorption qualities, biocompatibility, affordability, and simplicity. Additionally, they have high light absorption capability, which makes the nanostructures appealing candidates for the generation of hydrogen via photocatalytic water splitting for photoelectrochemical studies. The nanostructures are used in electrochemical applications, in which we focused on investigating the detection of numerous analytes. The nanostructures acted as high surface area supporting platforms as well as highly reactive surfaces, enhancing adsorption and analytes detection by immobilizing the enzyme. The morphology, substrate, scalability, selectivity, and stability of the fabricated biosensors were all thoroughly studied. The morphology of nanostructures and the underlying substrates have a significant impact on the sensitivity and detection limit of biosensors, according to our findings. The development of highly responsive systems to determine the different analytes contained in human blood, food and environment are progressing rapidly. The design and development of amperometric biosensors to monitor the concentration of several clinically important analytes such as glucose, cholesterol, lactate, pesticide, and hydrogen peroxide have been studied. To assess the photoelectrochemical (PEC) properties of the nanostructures, linear sweep voltammetry (LSV) and stability measurement also was performed and investigated.