Solid leather wastes (SLW) based porous carbons were used as the electrode material for supercapacitors in acid (H2SO4) medium. Electrochemical investigations indicate that samples activated at 900 °C shows a maximum capacitance of 1833 F/g at a scan rate of 1 mV/s in 1 M H2SO4 electrolyte. Moreover, SLW porous carbon electrodes show excellent cycling stability over 500 cycles at a constant current density of 20 A/g. Cyclic voltammetry (CV), galvanostatic charge/discharge (GCD) and electrochemical impedance spectroscopy (EIS) studies propose porous carbons developed from SLW could be an excellent electrode material for supercapacitors even in strong acid electrolyte medium. © 2017

John Kennedy L

Physics

School of Advanced Sciences

Chennai Campus

Konikkara N

Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

VIT is one of the top ranked private universities in India according to NIRF, THE and QS Rankings.&nbsp;Govt. of India has recognized&nbsp;VIT, Vellore as an&nbsp;Institution of Eminence. This has allowed VIT to take independent quality initiatives and move up in world ranking.

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VIT University

Materials Letters

Leather industries produce a large quantity of chromium containing wet blue leather solid waste (WBW), that are either thrown away or dumped in open lands causing environmental issues. These WBW are biologically resistant as a result of complexation between chromium (III) salts and the carboxyl groups of collagen. The objective of this study is to propose an unusual way to minimize environmental contamination routing through waste to energy concept, adopting cleaner methodologies. The research is also specifically focussed to bring in, new initiatives through interdisciplinary approach serving as a decisive key to transform wet blue leather wastes into a high performance supercapacitor electrode material. Electrochemical measurements such as cyclic voltammetry, galvanostatic charge discharge, and electrochemical impedance spectroscopy techniques using 1 M Na2SO4 aqueous electrolyte were performed to evaluate the suitability of the prepared carbon for supercapacitor applications. Na2SO4, is chosen as it can serve as neutral electrolyte, and has less corrosion behavior. The values of specific capacitance, specific energy, specific power and cycle stability for WBW activated at 900 °C (LSAC9) were 2203 Fg-1, 624.7 Whkg−1, 749.9 Wkg-1 and over 10,000 cycles respectively and are comparable with graphene like carbons. The performance of WBW porous carbons are consequence of micro-meso porosity and graphitic structure and are an initiative of waste to energy storage conversion concepts. © 2018 Elsevier Ltd

Journal of Cleaner Production

Value added porous carbon from leather wastes as potential supercapacitor electrode using neutral electrolyte

Abstract: Porous carbons prepared by carbonization of solid leather wastes were employed for supercapacitor applications using KOH electrolyte. Advanced instrumentation techniques were used to determine the physicochemical properties of the porous carbon samples. Three-electrode configuration was used to investigate the electrochemical properties of porous carbon electrodes through cyclic voltammetry studies, galvanostatic charge–discharge tests, electrochemical impedance spectroscopy (EIS) techniques in 1 M KOH electrolyte. Porous carbons exhibit high specific surface areas in a range of 613–716 m2 g−1, as well as superior energy storage capacity as electrodes for supercapacitors. Porous carbon electrodes activated at 900 °C exhibited specific capacitance up to 1800 F/g in alkali medium. All the solid leather waste carbons established stable cycle performance over 5000 cycles. These desirable capacitive performances enable solid leather waste-derived carbons as a source of new materials for low-cost energy storage devices as well as supercapacitors. This paper put forwards a new concept of ‘waste to value-added products’ that can be a helping hand for leather industries and its solid waste management disposal problems. The highlights of this research work suggest that leather industries could implement and make it feasible for commercialization. Graphical Abstract: [Figure not available: see fulltext.] © 2016, Springer-Verlag Berlin Heidelberg.

Clean Technologies and Environmental Policy

A new approach to solid waste management: fabrication of supercapacitor electrodes from solid leather wastes using aqueous KOH electrolyte

Utilization of crust leather waste (CLW) as precursors for the preparation of hierarchical porous carbons (HPC) were investigated. HPCs were prepared from CLW by pre-carbonization followed by chemical activation using KOH at relatively high temperatures. Textural properties of HPC's showed an extent of micro-and mesoporosity with maximum BET surface area of 716m(2)/g. Inducements of graphitic planes in leather waste derived carbons were observed from X-ray diffraction and HR-TEM analysis. Microstructure, thermal behavior and surface functional groups were identified using FT-Raman, thermo gravimetric analysis and FT-IR techniques. HPCs were evaluated for electrochemical properties by cyclic voltammetry (CV), galvanostatic charge/discharge (GCD) and electrochemical impedance spectroscopy (EIS) by three electrode system. CLC9 sample showed a maximum capacitance of 1960F/g in 1M KCl electrolyte. Results achieved from rectangular curves of CV, GCD symmetric curves and Nyquist plots show that the leather waste carbon is suitable to fabricate supercapacitors as it possess high specific capacitance and electrochemical cycle stability. The present study proposes an effective method for solid waste management in leather industry by the way of converting toxic leather waste to new graphitic porous carbonaceous materials as a potential candidate for energy storage devices.

Journal of Hazardous Materials

Preparation and characterization of hierarchical porous carbons derived from solid leather waste for supercapacitor applications

Nanoporous carbons (NPC) were prepared from crust leather wastes at temperatures 600, 700, 800 and 900 °C are labelled as CLC6, CLC7, CLC8 and CLC9 respectively. DC electrical conductivities of these NPCs were determined by two-probe method. The effects of compression pressure on electrical conductivity were studied by varying the compression pressure ranging from 17 to 611 KPa. An increase in values of electrical conductivity (EC) was noted for all samples with increase in compression pressures. CLC9 showed relatively higher conductivity values compared to the samples prepared at temperatures. At a compression pressure of 611 KPa, the EC values for CLC6, CLC7, CLC8 and CLC9 were 4.82×10-2, 4.26×10-1, 1.32, 3.7 Ω-1m-1 respectively. The temperature dependent conductivities of NPCs such as CLC6, CLC7, CLC8 and CLC9 revealed that the energy band gap (Eg) values to be 0.455, 0.253, 0.175, 0.145 eV respectively. This Eg values indicate that the NPCs fall under the category of low band gap semiconducting materials. Nitrogen adsorption/desorption isotherms show mixed type with Type I at low relative pressure range (P/Po) and Type IV at high P/Po range indicating that NPCs consists of both micropores (pore diameter, d &lt;2 nm) and mesopores (2 &lt; d &lt;50 nm) according to IUPAC classification. CLC8 possessed a maximum surface area of 716 m2/g estimated by Brunauer-Emmett-Teller (BET) method. Evolution of graphitic peaks was confirmed using Raman spectroscopy and X-ray diffraction techniques to support the electrical conduction mechanisms in NPCs. The surface morphology of the samples were observed using high resolution scanning electron microscope. Copyright © 2016 American Scientific Publishers.

Journal of Nanoscience and Nanotechnology

Electrical Conductivity Studies of Nanoporous Carbon Derived from Leather Waste: Effect of Pressure, Temperature and Porosity

Journal of Power Sources

A highly electronic conductive cobalt nickel sulphide dendrite/quasi-spherical nanocomposite for a supercapacitor electrode with ultrahigh areal specific capacitance

Journal	Data powered by TypesetMaterials Letters
Publisher	Data powered by TypesetElsevier BV
ISSN	0167-577X
Open Access	0