Mesoporous Ni-PANI composite electrode for electrochromic energy storage applications

다국어 초록 (Multilingual Abstract)

<P><B>Abstract</B></P> <P>Nanostructured mesoporous Ni-PANI thin film electrodes are fabricated on indium-doped tin oxide (ITO) conducting glass substrates using a pulse potential electro-polymerization technique. The Ni-PANI film is amorphous in nature and exhibits a mesoporous cauliflower like morphology. The multifunctional characteristics of Ni-PANI as an electrode for a smart supercapacitor are investigated using electrochemical and optical techniques in 0.5 M LiClO<SUB>4</SUB> +PC electrolyte. It is dark blue when it is charged at 0.7 V (vs SCE), and it is transparent when it is discharged at −0.7 V (vs SCE). Moreover, it can exhibit other colours like sky blue and parrot green in intermediate states. Specific discharge capacitance of 543 Fg<SUP>−1</SUP> and 267 Fg<SUP>−1</SUP> at a current density of 1 Ag<SUP>−1</SUP> is obtained for Ni-PANI and pure PANI respectively. The observed colouration efficiency is 45.9 cm<SUP>2</SUP>C<SUP>−1</SUP> for Ni-PANI and 35.1 cm<SUP>2</SUP>C<SUP>−1</SUP> for pure PANI at a wavelength of 630 nm. An outstanding optical modulation of 55.6% with a capacity retention of 90% after 5000 cycles is obtained for Ni-PANI electrode. The robust synthesis of Ni-PANI electrodes with efficient smart supercapacitor activity can be used as alternative materials in smart energy storage devices.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The NiO<SUB>x</SUB>-PANI exhibited multifunctional activity as energy storage and electrochromism. </LI> <LI> It is capable of sensing colour with respect to the level of energy stored. </LI> <LI> The device exhibits a colouration efficiency of 45.9 cm<SUP>2</SUP>C<SUP>-1</SUP> with an optical modulation of 55.6%. </LI> <LI> The high specific capacity is 543 F g<SUP>−1</SUP>, with a large potential window of 1.3 V. </LI> </UL> </P>