Evaluation of the PAni/B-doped diamond/CF ternary composite performance by varying the properties of constituent materia
- PDF / 795,498 Bytes
- 6 Pages / 612 x 792 pts (letter) Page_size
- 106 Downloads / 158 Views
Evaluation of the PAni/B-doped diamond/CF ternary composite performance by varying the properties of constituent materials Lilian M. Silva1, Dalva A. L. Almeida1, Silvia S. Oishi1, Andrea B. Couto1, Neidenêi G. Ferreira1. 1 Associated Laboratory of Sensors and Materials, National Institute for Space Research, São José dos Campos, SP, 12227-010, Brazil. ABSTRACT Polyaniline (PAni)/B-doped diamond/carbon fiber (CF) ternary composites were produced and characterized, aiming their application as electrodes for supercapacitor device. In order to optimize the composite properties, structurally different CF substrates, heat treated at 1000 and 2000ºC, were used to grown diamond films. Moreover, the diamond films were grown on CF in two different morphologies, boron doped micro and nanocrystalline diamond (BDD/BDND), by Hot Filament Chemical Vapor Deposition (HFCVD) technique. FEG-SEM images showed that PAni covered and enwrapped the diamond/CF surfaces, producing tridimensional electrodes. Raman spectra confirmed the PAni formation for all composites. Electrochemical characterizations indicated that the PAni/BDD/CF2000 composite has the highest current density and capacitance response among the studied composites combinations. In addition, it showed the most reversible oxidation and reduction processes, the greatest charge storage capacity as well as the lowest charge transfer resistance. INTRODUCTION Global energy demand has increased sharply at a worldwide scale, mainly due to an aggressive industrialization, rapid population growth and globalization, causing environmental pollution and energy sources scarcity [1,2]. Electrochemical energy storage devices have emerged as a substitute for fossil fuel energy as rechargeable and environmentally friendly devices [3]. Supercapacitors have been attracting a lot of attention since they present higher energy density than traditional capacitors and higher power density than other power devices [4]. The selection of suitable electrode material has been a challenge in energy storage devices. An ideal material should have high electrolyte accessible network along with high electrical conductivity, good mechanical and chemical stabilities. Among others, carbon materials with high surface area demonstrate high mechanical performance, chemical stability and high electrical conductivity [5]. However, their capacitances values are limited, which may be improved by adding a conductive polymer such as PAni that stands out not only for its high electrical conductivity and superior redox properties, but also for its easy synthesis, good environmental stability and relatively low cost. In addition, the carbonaceous material matrix acts like a template for the polymer growth, improving its stability during cycling process [6]. Thus, conductive polymers/carbonaceous materials composites may be an excellent electrode material for electrochemical capacitors. Therefore, in this work PAni/B-doped diamond/CF ternary composites were produced and characterized, aiming their application as electrode fo
Data Loading...
