Researchers remove silicon contamination from graphene to double its performance.
New research reveals why the "supermaterial" graphene has not transformed electronics as promised, and shows how to double its performance and finally harness its extraordinary potential.
Graphene is the strongest material ever tested. It's also flexible, transparent and conducts heat and electricity 10 times better than copper
After graphene research won the Nobel Prize for Physics in 2010 it was hailed as a transformative material for flexible electronics, more powerful computer chips and solar panels, water filters and bio-sensors. But performance has been mixed and industry adoption slow.
The RMIT University team inspected commercially-available graphene samples, atom by atom, with a state-of-art scanning transition electron microscope. Testing showed that silicon present in natural graphite, the raw material used to make graphene, was not being fully removed when processed.
Graphene was billed as being transformative, but has so far failed to make a significant commercial impact, as have some similar 2D nanomaterials
The testing not only identified these impurities but also demonstrated the major influence they have on performance, with contaminated material performing up to 50% worse when tested as electrodes.
The two-dimensional property of graphene sheeting, which is only one atom thick, makes it ideal for electricity storage and new sensor technologies that rely on high surface area. This study reveals how that 2D property is also graphene's Achilles' heel, by making it so vulnerable to surface contamination, and underscores how important high purity graphite is for the production of more pure graphene.
Using pure graphene, researchers demonstrated how the material performed extraordinarily well when used to build a supercapacitator, a kind of super battery
In collaboration with RMIT's Centre for Advanced Materials and Industrial Chemistry, the team then used pure graphene to build a versatile humidity sensor with the highest sensitivity and the lowest limit of detection ever reported.
These findings constitute a vital milestone for the complete understanding of atomically thin two-dimensional materials and their successful integration within high performance commercial devices.