Richard H. Friend

Research summary

Direct inkjet printing of complete polymer transistor circuits — including via-hole interconnections built from solution-processed polymer conductors, insulators, and self-organising semiconductors — was demonstrated, with substrate-surface-energy patterning steering water-based conducting-polymer droplets to define practical channel lengths of 5 µm, addressing the resolution bottleneck of continuous solution-based circuit manufacturing [1]. An all-polymer integrated optoelectronic device pairing a regioregular poly(3-hexylthiophene) FET (mobility 0.05-0.1 cm²/V·s, on/off > 10^6) with a similarly sized polymer LED demonstrated that conjugated-polymer transistors had reached amorphous-silicon-comparable performance and could drive emissive devices; the high mobility was attributed to extended polaron states formed by local self-organisation rather than variable-range hopping [3]. For organic photovoltaics, self-organising mixtures of discotic liquid-crystalline hexa-peri-hexabenzocoronene and a perylene dye were processed from solution into thin films with vertically segregated donor and acceptor phases and large interfacial area; the resulting diodes showed external quantum efficiencies above 34% near 490 nm, driven by efficient photoinduced charge transfer between hexabenzocoronene and perylene and by structurally optimised film morphology [4]. Perovskite light-emitting diodes were addressed with a bilayer design that boosted current efficiency to 42.9 cd/A — comparable to phosphorescent OLEDs — through two modifications: a slight excess of methylammonium bromide (MABr) suppressed the formation of metallic Pb° quenching centres, and a nanocrystal-pinning process spatially confined excitons within uniform MAPbBr3 nanograins averaging 99.7 nm in diameter [2].

Recent publications

1. Light-emitting diodes based on conjugated polymers1990 · Nature · 11341 citationsDOI
2. Electroluminescence in conjugated polymers1999 · Nature · 5968 citationsDOI
3. Two-dimensional charge transport in self-organized, high-mobility conjugated polymers1999 · Nature · 4589 citationsDOI
4. Bright light-emitting diodes based on organometal halide perovskite2014 · Nature Nanotechnology · 4367 citationsDOI
5. High-Resolution Inkjet Printing of All-Polymer Transistor Circuits2000 · Science · 3292 citationsDOI
6. Efficient photodiodes from interpenetrating polymer networks1995 · Nature · 3248 citationsDOI
7. Overcoming the electroluminescence efficiency limitations of perovskite light-emitting diodes2015 · Science · 2882 citationsDOI
8. Organic solar cells based on non-fullerene acceptors2018 · Nature Materials · 2794 citationsDOI
9. Integrated Optoelectronic Devices Based on Conjugated Polymers1998 · Science · 2726 citationsDOI
10. Self-Organized Discotic Liquid Crystals for High-Efficiency Organic Photovoltaics2001 · Science · 2351 citationsDOI

The lab page does not clearly state student acceptance status. Email the professor directly to confirm.

How to apply

Email Richard H. Friend 6-12 months before your application deadline. Read several recent papers and reference specific work in your message. Use our how to email a Japanese professor guide for the proven email structure.

For applications via MEXT scholarship: see our MEXT 2027 complete guide and university-specific University Recommendation track.

External profiles

• ORCID: https://orcid.org/0000-0001-6565-6308
• OpenAlex: openalex.org

Profile compiled from public sources (Researchmap, OpenAlex, Nagoya University faculty directory). Last refreshed 2026-05. Report incorrect information.