Scientists make single molecule diode

Single molecule diode schematicResearchers at Berkeley Lab and Columbia University have a made a high performance single molecule diode.

The scientists used a combination of gold electrodes and an ionic solution to make the diode, which they claim outperforms all predecessors by a factor of 50.

Back in 1974 two electronics scientists theorised that an asymmetric molecule could act as a rectifier and that led to a chase to develop a diode based on the theory.

Jeff Neaton, a senior faculty scientist at Berkeley Lab, said: “Using a single symmetric molecule, an ionic solution and two gold electrodes of dramatically different exposed surface areas, we were able to create a diode that resulted in a rectification ratio – the ratio of forward to reverse current at fixed voltage – in excess of 200, which is a record for single molecule devices.”

The scientists describe single molecule devices as the “ultimate limit in electronic miniaturisation”.

Diodes are one of the most prevalent components in electronics.

Neaton said the team expected the work to lead to ionic liquid gating in other contexts.

“These tiny molecular circuits are petri dishes for revealing and designing new routes to charge and energy flow at the nanoscale [level]. We’re just at the tip of the iceberg with what we can understand and control at these small length scales,” he said.