Jinho Chang

Morphology-Dependent Electrochemical Supercapacitor Properties of Indium Oxide

Electrodes of different morphology, i.e., nanospheres (NSs) and nanorods (NRs), made by chemically depositing indium oxide (In 2 O 3 ) on indium-tin oxide substrates were investigated for their electrochemical supercapacitive properties. The presence of nanosized pores and voids in In 2 O 3 electrode of NRs caused increase in redox reaction active sites, and ultimately, inner and outer charges than that of NSs In 2 O 3 electrode. Due to the combined effect of double-layer and pseudocapacitance, the specific capacitance of In 2 O 3 electrode composed of NRs was higher (105 F/g) than that of NS (7.6 F/g).

Direct Polymerized Polyaniline Nanostructures on Modified Indium-Tin Oxide Surface for Electrochemical Supercapacitors

Fundamental and experimental research on electrochemical supercapacitors ESs, also called ultracapacitors, has acquired considerable attention because of high power density and long cycle life compared to other electrochemical energy storage systems, including batteries. High power requirements for a short duration such as camera flash equipment, pulsed light generators, fire/smoke alarms, and backup power sources for computer memory are some of the decent applications of ESs. 1 The capacitance in ESs originates either from the charging or discharging of the electrical double layers or from the faradaic redox reactions. In the former case, the capacitance is derived from charge separation in the carbon-based materials, and in the latter, a faradaic process takes place due to redox reactions based on metal oxides and electronically conducting polymers. Among various conducting polymers, polyaniline PANI is one of the most promising materials for ESs because of its highcapacitive, eco-friendly characteristics, low cost, and easy processing. 2-5 In recent years, a great deal of research has concentrated on the fine-tuning synthesis of tubular morphologies by controlling reaction mechanisms. Among these studies, template-free chemical synthesis has been favored to polymerize PANI in the presence of large and bulky acids. For instance, a simple and practical development method using interfacial polymerization for making