Photosynthesis-inspired manufacturing of metal patterns (photobioform)

Lead Research Organisation: Loughborough University
Department Name: Sch of Mechanical and Manufacturing Eng


We have invented a new patterning process, which allows the formation of metal tracks onto non-conductive, plastic, flexible substrates, coating or powder such as polyimide or PEI (polyetherimide).

The process takes place in air environment at atmosphere pressure using low cost equipment.

The process involves the simple dipping of a substrate into a solution of potassium hydroxide, following by another dipping into a metal ions solution. The first dipping allows the opening of the imide ring chemical structure and insertion of the potassium ions into the broken chemical ring. The second dipping allows the swapping of the potassium ions with the ions of the electrolyte solution.

A laser or a flood exposure equipment using a photomask can be used to reduce the surface metal ions resulting in a gradient of metal ions, then the ions diffuse into the depleted zone and reach the surface where they reduce. A mild electron-donating agent has been used to accelerate the reduction of the ions. A thin layer of metal nanoparticles is then formed using this simple process, which can be used for subsequent electroless plating or for sensing purposes. Our preliminary feasibility studies published in IEEE transactions in Nanotechnology have demonstrated the concept using a synthetic agent at the cost of long exposure time and damage to the substrate.

We started using a bio-inspired material, chlorophyll extracted from spinach leaves, to speed up the photochemical process from 3 hours to 1 minute exposure using a blue light LED. We wish demonstrate that the use of chlorophyll can enable a truly manufacturing process that can be scaled up, and fully characterised for plastic electronics, PVs, moulded interconnects in electronics, sensing applications, in conjunction with additive manufacturing for multi-material manufacturing.


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Description This initial speculative feasibility project made new scientific breakthroughs and demonstrated the proof of concept around a highly novel concept of 'Green synthesis' methods which can selectively metallise a range of planar, flexible or 3D plastic parts with metal nanoparticles. This new manufacturing approach has the potential to enable low cost, sustainable and environmentally friendly manufacturing processes for the production of metal tracks, antimicrobial surfaces, and electrochemical sensors and actuators, which can benefit a range of industrial applications.

A phase II grant was secured from this project to further develop this work and generate industrially-driven proof of concept demonstrators. New Industrial partners have been brought into to further accelerate impact of this research: EP/N018265/1
Exploitation Route The key area of this research has developed a novel manufacturing process which has key application areas in electronics, healthcare, wearable devices and microsystems.
Sectors Electronics,Healthcare,Manufacturing, including Industrial Biotechology

Description This project has developed a method to 3D print plastic components where metal nano-particles can be selectively be reduced using light irradiation on the surface of the part. These parts have proven to have effective antimicrobial surfaces. As a result, a 3D printed water filter was fabricated and tested during the project. This particular water filter was shown to effectively eliminate cryptosporidium a waterborne pathogen that causes intestinal cryptosporidiosis. This simple to produce filter opens up a whole host of societal benefits for cleaner drinking water especially in developing countries that may lack the ability to cheaply treat water locally. The findings from this research secured a further three years of funding on a collaborative project (EP/N018265/2) with Heriot-Watt University, Merlin Circuit Technology, Renishaw and Blatchford. This work seeks to capitalise on the benefits of this process for applications covering electronic circuits, prosthetics and sensor systems.
First Year Of Impact 2015
Sector Agriculture, Food and Drink,Electronics,Healthcare,Manufacturing, including Industrial Biotechology
Impact Types Societal,Economic

Description A Platform for Hybrid Manufacturing Process research
Amount £1,675,629 (GBP)
Funding ID EP/P027687/1 
Organisation Engineering and Physical Sciences Research Council (EPSRC) 
Sector Public
Country United Kingdom
Start 06/2017 
End 06/2022
Description Manufacturing with Light II
Amount £699,524 (GBP)
Funding ID EP/N018222/1, EP/N018265/1, EP/N018265/2 
Organisation Engineering and Physical Sciences Research Council (EPSRC) 
Sector Public
Country United Kingdom
Start 10/2015 
End 10/2018
Description Additive Manufacturing and 3D printing workshop 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Industry/Business
Results and Impact The International Microelectronics and Packaging Society (IMAPS) Workshop on Additive Manufacturing (printing) for packaging was hosted by Dr. Robert Kay at Loughborough University on the 22nd October 2015. This workshop brought together a range of individuals primarily from industry in order to introduce them to the current developments and activities in 3D printing applied to the field of electronics. The workshop was split into a morning session which educated these new individuals into the field of Additive Manufacturing and then in the afternoon covered the latest developments in academia and industry around 3D printing for electronics manufacturing. The research findings from two EPSRC projects was also showcased at this event (EP/L017415/1 & EP/L022133/1). Besides the networking benefits from this event the investigators on this grant were able to establish new collaborations with industry on existing and future research activities. The event also raised the awareness of many of the research activities in this field currently being conducted by UK Universities.
Year(s) Of Engagement Activity 2015
Description Inspiring the next generation of students into Mechanical and Manufacturing Engineering. Smallpeice Trust event at University of Warwick for Year 12 Students, July 2017 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Schools
Results and Impact My aim was to deliver a talk that inspired students into engineering by me sharing my own personal experiences and research activities. The talk received many questions afterwards plus I received feedback by e-mail from some students thanking me for an enjoyable talk.
Year(s) Of Engagement Activity 2017
Description School Of Mechanical Engineering Seminar, 9th November 2017 Hybrid Additive Manufacturing of 3D Electronic Systems 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Professional Practitioners
Results and Impact 30 individuals from the School of Mechanical Engineering Attended an Invited Colloquium where Dr. Robert Kay presented his portfollio of EPSRC funded research
in the area of "Hybrid Additive Manufacturing of 3D Electronic Systems". This talk has sparked discussions to form new potential research collaborations in the field of Manufacturing Processes Research.
Year(s) Of Engagement Activity 2017