Air-stable and heating-free doping processes are crucial for advanced flexible electronics on plastic substrates. Researchers have developed a high-performance n-type organic dopant using the cationic dye Pyronin B.

This is achieved through a simple chemical reduction with NaBH4 in various organic non-polar solvents, transforming Pyronin B into its leuco form. The reduced Pyronin B (rPyB) interacts with carbon nanomaterials like graphene and PCBM via hydride-mediated electron transfer doping, confirmed by electron spin resonance (ESR) analysis.

When rPyB is coated onto graphene, the solvents are removed by evacuation without annealing, reducing graphene’s work function from 4.52 eV to 3.98 eV. Multiple coatings of rPyB ensure air stability for 90 days. This method allows for selective n-type doping using a PDMS stamp on a large-area graphene FET array, presenting a cost-effective approach for soft electronics. – Journal cover design by scapiens

https://pubs.rsc.org/en/content/articlelanding/2018/tc/c8tc02094a#!divAbstract