摘要
<p style="margin-left:10.0pt;"> <span style="font-family:Verdana;"><span style="font-family:Verdana;">We present the electrical and supercapacitive performance of graphene nanoplatelets in polymer nanocomposites and flexible solid state electrical double layer capacitors (EDLC) respectively. Graphene-doped poly</span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">(3,4-ethylenedioxythiophene) (PEDOT) coated polyethylene terephthalate (PET) and glass exhibited transmittance above 95% and electrical conductivity of 2.70 × 10<span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#f7f7f7;"="">ˉ</span></span><sup><span style="font-family:Verdana;">1</span></sup><span style="font-family:Verdana;"> S<span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#f7f7f7;"="">·</span>cm<span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#f7f7f7;"="">ˉ</span></span><sup><span style="font-family:Verdana;">1</span></sup><span style="font-family:Verdana;"> and 9.01 × 10<span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#f7f7f7;"="">ˉ</span></span><sup><span style="font-family:Verdana;">1</span></sup><span style="font-family:Verdana;"> S<span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#f7f7f7;"="">·</span>cm<span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#f7f7f7;"="">ˉ</span></span><sup><span style="font-family:Verdana;">1</span></sup><span style="font-family:Verdana;"> respectively. Graphene loaded polymethyl methacrylate (PMMA) and polystyrene (PS) nanocomposites showed electrical conductivity as high as 2.11 × 10<span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#f7f7f7;"="">ˉ</span></span><sup><span style="font-family:Verdana;">1</span></sup><span style="font-family:Verdana;"> S<span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#f7f7f7;"="">·</span>cm<span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#f7f7f7;"="">ˉ</span></span><sup><span style="font-family:Verdana;">1</span></sup><span style="font-family:Verdana;"> at low loadings of 2</span></span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">wt%. The use of graphene was necessitated by the need to increase the EDLC capacitance and energy density since it provides high effective surface area. The polymer gel membrane made from polyvinylidene fluoride-co-hexafluoropropylene (PVDF-co-HFP) and the Ionic Liquid (IL) 1-butyl-3-methylimidazolium hexafluorophosphate exhibited high porosity which made it suitable for use as separator in the EDLC. The highes</span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">t recorded specific capacitance was 133.82 F/g which can be attributed to the porosity of the IL containing PVDF-co-HFP membrane and the large surface area of the graphene electrodes. At an operating voltage of 3.5 V the energy density was found to be 56.92 Wh<span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#f7f7f7;"="">·</span>Kg<span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#f7f7f7;"="">ˉ</span></span><sup><span style="font-family:Verdana;">1</span></sup><span style="font-family:Verdana;">. All chemicals were research grade and were obtained from Sigma Aldrich.</span></span></span></span> </p>
<p style="margin-left:10.0pt;"> <span style="font-family:Verdana;"><span style="font-family:Verdana;">We present the electrical and supercapacitive performance of graphene nanoplatelets in polymer nanocomposites and flexible solid state electrical double layer capacitors (EDLC) respectively. Graphene-doped poly</span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">(3,4-ethylenedioxythiophene) (PEDOT) coated polyethylene terephthalate (PET) and glass exhibited transmittance above 95% and electrical conductivity of 2.70 × 10<span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#f7f7f7;"="">ˉ</span></span><sup><span style="font-family:Verdana;">1</span></sup><span style="font-family:Verdana;"> S<span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#f7f7f7;"="">·</span>cm<span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#f7f7f7;"="">ˉ</span></span><sup><span style="font-family:Verdana;">1</span></sup><span style="font-family:Verdana;"> and 9.01 × 10<span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#f7f7f7;"="">ˉ</span></span><sup><span style="font-family:Verdana;">1</span></sup><span style="font-family:Verdana;"> S<span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#f7f7f7;"="">·</span>cm<span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#f7f7f7;"="">ˉ</span></span><sup><span style="font-family:Verdana;">1</span></sup><span style="font-family:Verdana;"> respectively. Graphene loaded polymethyl methacrylate (PMMA) and polystyrene (PS) nanocomposites showed electrical conductivity as high as 2.11 × 10<span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#f7f7f7;"="">ˉ</span></span><sup><span style="font-family:Verdana;">1</span></sup><span style="font-family:Verdana;"> S<span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#f7f7f7;"="">·</span>cm<span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#f7f7f7;"="">ˉ</span></span><sup><span style="font-family:Verdana;">1</span></sup><span style="font-family:Verdana;"> at low loadings of 2</span></span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">wt%. The use of graphene was necessitated by the need to increase the EDLC capacitance and energy density since it provides high effective surface area. The polymer gel membrane made from polyvinylidene fluoride-co-hexafluoropropylene (PVDF-co-HFP) and the Ionic Liquid (IL) 1-butyl-3-methylimidazolium hexafluorophosphate exhibited high porosity which made it suitable for use as separator in the EDLC. The highes</span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">t recorded specific capacitance was 133.82 F/g which can be attributed to the porosity of the IL containing PVDF-co-HFP membrane and the large surface area of the graphene electrodes. At an operating voltage of 3.5 V the energy density was found to be 56.92 Wh<span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#f7f7f7;"="">·</span>Kg<span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#f7f7f7;"="">ˉ</span></span><sup><span style="font-family:Verdana;">1</span></sup><span style="font-family:Verdana;">. All chemicals were research grade and were obtained from Sigma Aldrich.</span></span></span></span> </p>
