A team of Chinese scientists has made ground-breaking development of a new device – a 3D hollow-cone structure, increasing solar-thermal conversion efficiency.
The device is named ‘Artificial Transpiration’ and is graphene oxide film based. Zhu Jia and his team from the Nanjing University in China were inspired by the transpiration process and 3D morphology of plants, which is seamlessly demonstrated in the 3D artificial transpiration device that comprises a 3D hollow cone absorber connected with a 1D water path.
The special 1D water path can lower the operating temperature, reducing radiation, convection, and conduction losses. The cone structure can collect more sunlight than a flat device throughout the day, as around 10-50% of sunlight is diffusive. The team of scientists reiterated that the device performs better outside the lab. Thus, the device can enhance the solar-thermal conversion rate to 85%, which is much higher than the 40% rate of common devices. The device also has a fast thermal response, which reduces detrimental factors in real applications like inconsistent sunlight due to partial cloud cover.
New possibilities in the utilization of solar energy are expected to open with this device. Mr Zhu and his fellow-researchers applied this structure first to solar waste-water treatment, which demonstrated that clean water could not only be retrieved, but recycling of heavy metals such as copper and cadmium could also be recycled with a minimal carbon footprint. The structure could be further optimized in the future to achieve a longer life and recycle more heavy metals.