Energy Harvesting Organic Diodes

Developing rectifier circuits using organic diodes

Photograph of flexible organic diodes
Photograph of organic diodes capable of energy harvesting at 13.56 MHz

I worked as a Research Associate in the lab of Professor Henning Sirringhaus at the University of Cambridge from 2015 to 2016. My research focused on understanding and applying organic materials in the context of printed and flexible electronics. I developed organic rectifiers for use in smart packaging.

Developing energy harvesting circuits for smart packaging

Energy harvesting circuits (circuits which convert radio waves into power) are found in identity cards and contactless payment systems, as well as in livestock and inventory tracking tags. These radio tags use embedded silicon chips to perform the role of capturing energy from the radio signal. While cheap to manufacture, the expense of joining the silicon chip to the radio antenna keeps the price per tag relatively high.

Printed organic electronics, an additive manufacturing approach, has the potential to undercut the costs associated with silicon attachment. I developed conjugated polymer-based organic diodes, capable at operating at 13.56 MHz, a key requirement for compatibility with existing standards. These diodes were used in a full-wave rectifier to provide sufficient power to drive a complex logic circuit and e-ink display outputs.1

Read our paper summarising the performance of our energy harvesting circuit

Industry collaboration

I worked within the SECURE project (Secure tags Enabled by near field Communications United with Robust Electronics), a collaboration between flexible-electronics manufacturer FlexEnable Ltd, the banknote printing company De La Rue, and the University of Cambridge. This gave me valuable insight into market forces and requirements.

  1. Figure reprinted with permission from: Higgins SG, Agostinelli T, Markham S, Whiteman R, Sirringhaus H, Organic Diode Rectifiers Based on a High-Performance Conjugated Polymer for a Near-Field Energy-Harvesting Circuit, 2017. Advanced Materials, 1703782. Copyright © 2017, WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. DOI: 10.1002/adma.201703782 ↩︎