A novel process is reported which produces an asymmetric supercapacitor through the complete recycling of end-of-life lithium ion batteries.The electrodic powder recovered by industrial scale mechanical treatment of s...A novel process is reported which produces an asymmetric supercapacitor through the complete recycling of end-of-life lithium ion batteries.The electrodic powder recovered by industrial scale mechanical treatment of spent batteries was leached and the dissolved metals were precipitated as mixed metals carbonates.Nanowires battery-type positive electrodes were produced by electrodeposition into nanoporous alumina templates from the electrolytic baths prepared by dissolution of the precipitated carbonates.The impact of the different metals contained in the electrodic powder was evaluated by benchmarking the electrochemical performances of the recovered nanowires-based electrodes against electrodes produced by using high-purity salts.Presence of inactive Cu in the nanowires lowered the final capacitance of the electrodes while Ni showed a synergistic effect with cobalt providing a higher capacitance with respect to synthetic Co electrodes.The carbonaceous solid recovered after leaching was indepth characterized and tested as negative electrode.Both the chemical and electrochemical characterization indicate that the recovered graphite is characterized by the presence of oxygen functionalities introduced by the leaching treatment.This has led to the obtainment of a recovered graphite characterized by an XPS C/O ratio,Raman spectrum and morphology close to literature reports for reduced graphene oxide.The asymmetric supercapacitor assembled using the recovered nanowires-based positive electrodes and graphite as negative electrodes has shown a specific capacitance of 42 F g^(-1), computed including the whole weight of the positive electrode and recovered graphite,providing a maximum energy density of ~9 Wh kg^(-1) and a power density of 416 W kg^(-1) at 2.5 mA cm^(-2).展开更多
Incomprehension concerning heavy metal containing finished solid leather wastes leads to environmental pollution.Conversion of these solid leather waste into energy and resource efficient products proves to be challen...Incomprehension concerning heavy metal containing finished solid leather wastes leads to environmental pollution.Conversion of these solid leather waste into energy and resource efficient products proves to be challenging.However,leather microfibres(LMF)were isolated from these heavy metal containing finished solid leather wastes.These heavy metal contain LMF further processed into metal reduction LMF.The metal reduction LMF were investigated for their heavy metal removal efficiency and toxicity analysis.The Cr(III)and Cr(VI)content of LMF was<1000μg/mL and<800μg/mL,respectively.Toxicity estimation was proved that the LMF had less than 1%.The study attempt to prepare reconstituted fibric materials(RFM)from metal reduction LMF and cellulose nanofibres(CNF).RFM were characterized for their physicochemical and mechanical properties.Hence,the study has proved a novel concept of RFM production which is recyclable,environmental friendly and cost effective.展开更多
文摘A novel process is reported which produces an asymmetric supercapacitor through the complete recycling of end-of-life lithium ion batteries.The electrodic powder recovered by industrial scale mechanical treatment of spent batteries was leached and the dissolved metals were precipitated as mixed metals carbonates.Nanowires battery-type positive electrodes were produced by electrodeposition into nanoporous alumina templates from the electrolytic baths prepared by dissolution of the precipitated carbonates.The impact of the different metals contained in the electrodic powder was evaluated by benchmarking the electrochemical performances of the recovered nanowires-based electrodes against electrodes produced by using high-purity salts.Presence of inactive Cu in the nanowires lowered the final capacitance of the electrodes while Ni showed a synergistic effect with cobalt providing a higher capacitance with respect to synthetic Co electrodes.The carbonaceous solid recovered after leaching was indepth characterized and tested as negative electrode.Both the chemical and electrochemical characterization indicate that the recovered graphite is characterized by the presence of oxygen functionalities introduced by the leaching treatment.This has led to the obtainment of a recovered graphite characterized by an XPS C/O ratio,Raman spectrum and morphology close to literature reports for reduced graphene oxide.The asymmetric supercapacitor assembled using the recovered nanowires-based positive electrodes and graphite as negative electrodes has shown a specific capacitance of 42 F g^(-1), computed including the whole weight of the positive electrode and recovered graphite,providing a maximum energy density of ~9 Wh kg^(-1) and a power density of 416 W kg^(-1) at 2.5 mA cm^(-2).
基金Dr.Senthil Rethinam acknowledges the funding support granted by the 2232-International Fellowship for Outstanding Researcher Program of TUBITAK(Project No:118C350).
文摘Incomprehension concerning heavy metal containing finished solid leather wastes leads to environmental pollution.Conversion of these solid leather waste into energy and resource efficient products proves to be challenging.However,leather microfibres(LMF)were isolated from these heavy metal containing finished solid leather wastes.These heavy metal contain LMF further processed into metal reduction LMF.The metal reduction LMF were investigated for their heavy metal removal efficiency and toxicity analysis.The Cr(III)and Cr(VI)content of LMF was<1000μg/mL and<800μg/mL,respectively.Toxicity estimation was proved that the LMF had less than 1%.The study attempt to prepare reconstituted fibric materials(RFM)from metal reduction LMF and cellulose nanofibres(CNF).RFM were characterized for their physicochemical and mechanical properties.Hence,the study has proved a novel concept of RFM production which is recyclable,environmental friendly and cost effective.