Light-Emitting Electrochemical Cells of Single Crystal Hybrid Halide Perovskite with Vertically Aligned Carbon Nanotubes Contacts

TL;DR

This paper reports a novel light-emitting electrochemical cell using single crystal hybrid halide perovskite with vertically aligned carbon nanotubes as electrodes, demonstrating bright green emission and potential for stable optoelectronic devices.

Contribution

The study introduces a new device architecture combining perovskite single crystals with CNT electrodes, enabling efficient ion migration and bright light emission.

Findings

Achieved bright green light emission up to 1800 cd/m2 at room temperature.

Demonstrated in operando formation of p-i-n heterojunction via ion migration.

Showed potential for stable perovskite-based optoelectronic devices.

Abstract

Based on the reported ion migration under electric field in hybrid lead halide perovskites we have developed a bright, light emitting electrochemical cell with CH3NH3PbBr3 single crystals directly grown on vertically aligned carbon nanotube (VACNT) forests as contact electrodes. Under the applied electric field, charged ions in the crystal drift and accumulate in the vicinity of the electrodes, resulting in an in operando formed p-i-n heterojunction. The decreased interface energy barrier and the strong charge injection due to the CNT tip enhanced electric field, result in a bright green light emission up to 1800 cd/m2 at room temperature (average = 60 cd/m2). Beyond the light emission, this original device architecture points to the possibility of implementing vertically aligned CNTs as electrodes in operationally-stable perovskite-based optoelectronic devices.