The development of cost-effective and efficient energy-storage devices,such as supercapacitors with enhanced electrochemical properties,is highly needed for the future.Therefore,the highly porous surface area of wheat...The development of cost-effective and efficient energy-storage devices,such as supercapacitors with enhanced electrochemical properties,is highly needed for the future.Therefore,the highly porous surface area of wheat straw,which is activated carbon(AC)derived through chemical activation,is being used to develop electrodes.AC with a surface area of 1093.46 m^(2)/g was used for electrode fabrication by mixing proportions of 80%,90%,100%,and 0%AC with polyvinylidene fluoride and N-methyl-2-pyrrolidone solution on different current collectors such as copper,stainless steel,and aluminum.The electrochemical analysis of the developed electrodes and symmetric electrochemical double-layer capacitors was performed against a silver/silver chloride reference electrode by using cyclic voltammetry,galvanostatic charge-discharge,and electrochemical impedance spectroscopy.The specific capacitance of the electrodes,as shown in cyclic voltammogram curves,is 305.2,287,and 256.2 F/g.The galvanostatic charge-discharge curves display 281,244.5,and 226.5 F/g at 0.5 A/g,and 247,206,and 189 F/g at 1 A/g for copper,aluminum,and stainless steel current collectors,respectively.The symmetric electrochemical double-layer capacitors,made with 90%AC and copper current collectors,exhibited quasi-rectangular curves with specific capacitances of 219.4,172.7,and 132.4 F/g.Different areas of the current collector in supercapacitors increase the active material deposit,enabling more charge and ions to accumulate,resulting in improved charge-transfer resistance.展开更多
Pyrolysis is a thermal conversion process in the absence of air to derive energy components from the residues.Renewable-energy technologies will play a major role in addressing future challenges related to environment...Pyrolysis is a thermal conversion process in the absence of air to derive energy components from the residues.Renewable-energy technologies will play a major role in addressing future challenges related to environmental safety and energy security.One of the many easily available renewable energy sources is biomass-an organic material that is thought to be carbon-neutral.Pyrolysis technology is a thermochemical process that can be used to produce useful products from biomass,such as biochar,bio-oil and combustible pyrolysis gases.The structure and relative product yield are impacted by the pyrolysis method employed.This article evaluates different approaches for biomass pyrolysis.Fast,slow and advanced pyrolysis methods using various pyrolyser reactors have been studied in the literature and are provided to increase the variety and use of these methods in upcoming studies and research.Slow pyrolysis can lead to increased ecological well-being,as it increases the amount of biochar produced using auger and rotary-kiln reactors.Rapid pyrolysis,mainly in fluidized-bed reactors with bubbling and rotating circulation,can be used to obtain bio-oil.Advanced pyrolysis methods offer a good probability of yielding great prosperity for specific applications.The selection of a pyrolysis process is based on the required output in terms of solid,liquid and gaseous fuels,and the parameter plays a crucial role in the pyrolysis performance.展开更多
文摘The development of cost-effective and efficient energy-storage devices,such as supercapacitors with enhanced electrochemical properties,is highly needed for the future.Therefore,the highly porous surface area of wheat straw,which is activated carbon(AC)derived through chemical activation,is being used to develop electrodes.AC with a surface area of 1093.46 m^(2)/g was used for electrode fabrication by mixing proportions of 80%,90%,100%,and 0%AC with polyvinylidene fluoride and N-methyl-2-pyrrolidone solution on different current collectors such as copper,stainless steel,and aluminum.The electrochemical analysis of the developed electrodes and symmetric electrochemical double-layer capacitors was performed against a silver/silver chloride reference electrode by using cyclic voltammetry,galvanostatic charge-discharge,and electrochemical impedance spectroscopy.The specific capacitance of the electrodes,as shown in cyclic voltammogram curves,is 305.2,287,and 256.2 F/g.The galvanostatic charge-discharge curves display 281,244.5,and 226.5 F/g at 0.5 A/g,and 247,206,and 189 F/g at 1 A/g for copper,aluminum,and stainless steel current collectors,respectively.The symmetric electrochemical double-layer capacitors,made with 90%AC and copper current collectors,exhibited quasi-rectangular curves with specific capacitances of 219.4,172.7,and 132.4 F/g.Different areas of the current collector in supercapacitors increase the active material deposit,enabling more charge and ions to accumulate,resulting in improved charge-transfer resistance.
基金supported by the Department of Renewable Energy Engineering,College of Technology and Engineering,MPUAT,Udaipur,Rajasthan,India.
文摘Pyrolysis is a thermal conversion process in the absence of air to derive energy components from the residues.Renewable-energy technologies will play a major role in addressing future challenges related to environmental safety and energy security.One of the many easily available renewable energy sources is biomass-an organic material that is thought to be carbon-neutral.Pyrolysis technology is a thermochemical process that can be used to produce useful products from biomass,such as biochar,bio-oil and combustible pyrolysis gases.The structure and relative product yield are impacted by the pyrolysis method employed.This article evaluates different approaches for biomass pyrolysis.Fast,slow and advanced pyrolysis methods using various pyrolyser reactors have been studied in the literature and are provided to increase the variety and use of these methods in upcoming studies and research.Slow pyrolysis can lead to increased ecological well-being,as it increases the amount of biochar produced using auger and rotary-kiln reactors.Rapid pyrolysis,mainly in fluidized-bed reactors with bubbling and rotating circulation,can be used to obtain bio-oil.Advanced pyrolysis methods offer a good probability of yielding great prosperity for specific applications.The selection of a pyrolysis process is based on the required output in terms of solid,liquid and gaseous fuels,and the parameter plays a crucial role in the pyrolysis performance.
