Centre for Nano and Soft Matter Sciences (CeNS) Researchers Develop Sunlight-Powered Supercapacitor

Key facts

• Researchers at the Centre for Nano and Soft Matter Sciences (CeNS), Bengaluru, an autonomous institute under the Department of Science and Technology (DST), have developed a photo-rechargeable supercapacitor that captures and stores solar energy in a single integrated system.
• The technology utilises binder-free nickel–cobalt oxide (NiCo₂O₄) nanowires grown directly on nickel foam through an in situ hydrothermal process to act simultaneously as a solar harvester and an electrode.
• Under illumination, the electrode demonstrated a 54 per cent increase in capacitance, rising from 570 to 880 millifarads per square centimetre at a current density of 15 milliamperes per square centimetre.
• The electrode exhibited high durability by retaining 85 per cent of its original capacity after 10,000 charge–discharge cycles.
• An asymmetric photo-supercapacitor using activated carbon as the negative electrode delivered a stable output voltage of 1.2 volts and maintained 88 per cent capacitance retention after 1,000 photo-charging cycles.
• The study, published in the journal Sustainable Energy & Fuels, revealed that nickel substitution narrows the band gap to approximately 1.67 eV and induces half metallic behaviour for faster charge transport.
• The device is designed to function in remote regions without electrical grid access, reducing dependence on fossil fuels and conventional batteries.