# Laser‐Patternable and Stretchable Metal Electrodes Using Metal–Amine Coordination Complexes

## TL;DR

Researchers developed a stretchable metal electrode using metal-amine coordination complexes, enabling high stretchability and durability for flexible electronics.

## Contribution

A novel stretchable electrode (MACE) is introduced, leveraging metal-amine coordination complexes for enhanced stretchability and durability without conventional treatments.

## Key findings

- MACEs exhibit up to 70% stretchability and durability under 40% strain for 10,000 cycles.
- Direct laser patterning allows for versatile pattern formation and adjustable stretchability.
- A reversible soft actuator with a simple structure was demonstrated using MACE properties.

## Abstract

Coordination bonding is a crucial interaction between heteromaterials that enhances both mechanical toughness and stretchability, with mussels serving as a natural example of thriving in harsh marine environments due to this interaction. However, stretchable electronic materials based on this fundamental interaction have been rarely reported. In this study, a stretchable electrode, called the metal–amine coordination‐complex‐based electrode (MACE) is introduced, which involves the formation of coordination complexes between a solid metal and an organic layer. MACEs are based on a single Au layer with a thickness of a few tens of nanometers, yet they exhibit excellent stretchability of up to 70% and high durability under strain at 40% for 10 000 cycles without conventional treatments, such as pre‐stretching the substrate. Additionally, the direct laser patterning process on the metal film allows for high versatility in forming desirable patterns and adjusting stretchability. Furthermore, by utilizing the mechanical and electrical properties of MACE, a reversible soft actuator with a simple laminated structure is demonstrated. This approach, based on the formation of coordination complexes between heteromaterials, provides insights into fully mechanically stretchable electronics that achieve both softness and toughness simultaneously.

A stretchable electrode, called the metal–amine coordination‐complex‐based electrode (MACE), is introduced, which involves the formation of coordination complexes between a metal and an organic layer. MACE exhibits excellent stretchability of up to 70% and stability under both air and wet conditions. Through direct laser processing, MACE forms desirable patterns under dry conditions and allows for the adjustment of stretchability.