Scientists at the Centre for Nano and Soft Matter Sciences (CeNS) in Bengaluru, India, have created a sunlight‑powered supercapacitor capable of harvesting and storing solar energy in one device, marking a notable advance in low‑cost, self‑sustaining power technologies.
The Ministry of Science & Technology announced the breakthrough, highlighting its potential for next‑generation portable and off‑grid applications.
The device, named a photo‑capacitor, brings together the functions of a solar cell and an energy‑storage unit. Unlike conventional solar systems, which rely on separate components and additional electronics to manage power flow, this integrated design aims to cut energy losses, reduce system size and simplify operation.
The researchers say the technology could support a wide range of devices, from wearables to standalone sensors, particularly in areas without reliable access to the electricity grid. By capturing sunlight and storing the resulting charge simultaneously, the device removes the need for complex circuitry that typically increases cost and reduces efficiency.
The team, led by Dr Kavita Pandey, achieved the performance boost using binder‑free nickel‑cobalt oxide (NiCo₂O₄) nanowires grown uniformly on nickel foam through an in situ hydrothermal method. These nanowires, only a few nanometres wide, form a porous 3D network that absorbs light and stores charge with high efficiency.
Testing showed a 54% rise in capacitance under illumination — from 570 to 880 mF cm⁻² at 15 mA cm⁻² — driven by effective light‑induced charge transfer within the nanowire structure. Even after 10,000 charge–discharge cycles, the electrode retained 85% of its capacity, underscoring its durability for long‑term use.
The work was published in the journal Sustainable Energy & Fuels.
