The ever-increasing demand for small, portable electronic devices such as electronic wristbands has created a gap in the energy storage market. These devices are small, and often do not have room for a standard battery or supercapacitor in their electric circuitry. Instead, researchers at Griffith University have developed a novel process for fabricating graphene-based micro-supercapacitors that can be directly integrated into the device’s electric circuit.
Supercapacitors charge quickly, store a large amount of energy, and have a much longer operational life than conventional batteries, making them suitable for use in modern devices. Graphene is uniquely suited for developing next generation supercapacitors due to its tremendous elasticity, mechanical strength, high surface area, and minimal weight. However, graphene is also difficult to work with and easily damaged, and scientists have struggled to translate its potential from the laboratory into the real world.
The research team, led by Associate Professor Francesca Iacopi, have been working with the support of ANFF-Q to overcome these issues by growing the graphene directly onto the silicon wafer. First, a thin layer of silicon carbide is grown on the silicon wafer using a heat treatment with the desired surface pattern achieved through photolithography and etching techniques. Graphene can then be evolved on top of the silicon carbide using metal catalysts and a high temperature graphitisation method under vacuum conditions. Following this process, the team were able to achieve a world first: the fabrication of graphene-based micro-devices using silicon carbide films on silicon wafers.
Further work will focus on optimising the synthesis conditions and device dimensions to further improve performance. The novel techniques used in the project can be directly applied in the micro-fabrication industry to fabricate practical electronic components for integrated, high performance energy storage in small portable devices.
The research team is now working with US Air Force Research Laboratory to continue developing the technology, and this work also offers Australia the chance to develop a local industry around the low-cost manufacture of high performing micro-sized energy units.
