# 1690-Fold enhanced electrochemiluminescence of gold nanoclusters via Zn2+ induced aggregation

## TL;DR

Scientists developed a method to greatly boost the light emission of gold nanoclusters using zinc ions, making them much brighter for potential applications.

## Contribution

The study introduces a novel dual-enhancement strategy using Zn2+ to amplify electrochemiluminescence in gold nanoclusters.

## Key findings

- Zn2+ induces aggregation of gold nanoclusters, enhancing electrochemiluminescence by 1690-fold.
- Zn2+ improves ligand rigidification and promotes electron transfer, contributing to the enhancement.
- The method can be used to design brighter electrochemiluminescent materials.

## Abstract

Herein, a zinc ion (Zn2+)-induced aggregation strategy is proposed for 1690-fold enhanced electrochemiluminescence (ECL) from d-penicillamine (DPA)-capped gold nanoclusters (AuNCs), and the aggregation-induced ECL (AIECL) is a multiplicative effect of two enhancing factors. One is the improved ligand rigidification of Zn2+-induced aggregation of AuNCs, i.e. Zn2+-AuNCs. The Zn2+ of Zn2+-AuNCs can reduce the vibration and rotation of DPA, suppress non-radiative decay, and result in ∼17-fold enhanced emission with photoluminescence (PL) as control. The other is the promoted electron transfer by Zn2+–DPA bonds, which can enhance charge annihilation with the assistance of energy level alignment between AuNCs and the Zn2+–DPA bond, further amplifying ECL by another ∼100-fold. The dual-enhanced AIECL strategy can be utilized to design even brighter ECL luminophores.

Schematic illustration of 1690-fold enhanced electrochemiluminescence of gold nanoclusters via Zn2+ induced aggregation.