If you read Hackaday regularly, you’ve probably heard that you can use a LASER to create graphene. There’s been a bit of research on how to make practical graphene supercapacitors using the technique (known as LIG or LASER-induced graphene). Researchers at Rice University have been working on this, and apparently they’ve had significant success inducing graphene capacitors on a Kapton substrate. The team has published a paper in Advanced Materials (which is behind a paywall) about their work.
In particular, Rice claims that they have easily produced supercapacitors with an energy density of 3.2 mW/cubic centimeter (that’s what the University’s website reports; they probably mean mW-hours/cubic centimeter) with capacitances near one millifarad per square centimeter. A key benefit of the construction method is that the capacitors continued to work after researchers bent them 10,000 times. A flexible capacitor is useful in wearable devices that would often flex, or in a device like a cell phone that could bend in your back pocket as you sit.
While it is easy to grow graphene with a LASER (we’ve even seen it done with a DVD burner more than once), the interesting part of the Rice team’s research seems to be their use of electrodeposition of manganese dioxide, ferric oxyhydroxide, or polyaniline to create composite positive and negative electrodes. You can see a short video about the new technique below (and that’s certainly not a DVD burner).
Thanks [lethal popcorn] for the tip.