Conductive oxide-based dispersions from non-critical raw materials for functional nanoinks

Introduction

Transparent conductive oxides (TCOs) inks combine high transparency in the visible spectrum and high electrical conductivity with the benefits of solution processing for printable electronics. The most promising TCO, Sn:In2O3 (ITO), is currently being replaced in the transparent conductive inks market due to the supply risk associated with ITO.

Alternatives to ITO

Alternatives to ITO range from:

• Silver flakes
• Copper pastes
• Graphene and other carbon-based materials

However, the remarkable environmental stability, chemical tunability, and optoelectronic properties of TCOs remain unbeaten. Hence, it is time to invest in good alternative TCO inks made from non-critical raw materials.

Challenges in TCO Nanocrystals

In CONDINKS, we have identified some of the major issues limiting the performance of TCO nanocrystals in conductive inks, which are related to:

1. Their electronic structure and depletion layer formation
2. Dopant segregation

Dopants that are segregated on the surface may remain inactive and, hence, do not contribute to conductivity. Conversely, if dopants are segregated in the core, it might result in large depletion layers. Both effects significantly influence thin film conductivity, particularly on the nanoscale.

Objectives of CONDINKS

The solution offered by CONDINKS is based on two objectives:

1. Making conductive inks from non-critical raw materials with properties that compete with benchmark systems through nanoscale dopant engineering.
2. Upscaling the produced materials, with initial attempts towards reactors in aqueous-based flow synthesis processes.

Innovation and Team

The breakthrough innovation of our product is immediately evident: similar (or superior) properties to commercially available materials with lower cost and lower supply risk. CONDINKS has assembled a team of researchers with industrial support to tackle the ambitious goal of developing conductive inks based on non-critical raw materials, enhanced through dopant engineering.