Novel display technologies increasingly use haptic materials that permit multifunctional performance that includes mechanical feedback, thermal or optical, roughness or other surface control. There is an exciting range of new materials and materials structures/systems that are being considered for next generation touch screens incorporating haptic style feedback to pressure, temperature, touch for a more positive and rewarding response for the user. These 'active' materials are often based on piezoelectric polymers, thin film piezoelectrics and quantum tunnelling composites. When these materials are stressed, they produce useful electrical currents and when a voltage is applied to them then they produce valuable changes in shape. One significant barrier to the roll-out of such new technologies is the lack of high activity material suffering from poor reliability and poor uniformity, which becomes really important when those materials are machined and processed at small length scales. As the active materials are integrated within ever more complex designs needed for e.g. touch screens, hydrophones or energy harvesting modules, it becomes imperative to be able to characterise the full 3D volume of those active elements. There are currently no industrially scalable measurement tools which can accurately assess important physical properties from a 3D volume of these active materials. In this proposal we aim to address this barrier by developing and then commercialising a new measurement tool which has been shown to work in principle following a European Metrology Research Project (2020-ADVENT). Considerable risk still exists because we are unsure if our all-optical probe can be used in conjunction with a new interrogation methodology which would permit rapid and accurate assessment of materials performance, reliability, uniformity and functional properties throughout the 3D volume of the material. Such a tool would be revolutionary in assessing functional materials for these and many other applications where a 2-1/2D to 3D response/feedback is desired. There are no other tools that can accomplish such a solution and Electrosciences Ltd will rapidly commercialise the new product, should this proposal be awarded, and the technical R&D prove successful. The new tool would accelerate new materials, compositions and systems development cycles, and hence reduce costs, because accurate and traceable measurement data would be available directly linking material to function (e.g. sensing, actuation, transduction) through to integrated design within the new devices. This is how this project would support the UK supply chain supporting haptics and touch screen technologies, hydrophone and the emerging energy harvesting sectors.

The EU Green Deal is supported by the EU research initiative BATTERY 2030+. EU battery and automotive industries face strong competition for high capacity energy storage technologies for use in electric vehicles, portable devices and grid stabilisation. Despite recent advances in battery performance, capacities and lifetimes are still too poor for many key applications. To accelerate innovation by materials and device manufacturers, new metrology is urgently required. This project supports the development of in operando techniques, supported by standardised ex-situ analysis and electrochemical measurements, to enable beyond state-of-the-art materials characterisation.

In the development of novel sensors, actuators and transducers, accurate materials property evaluation is key to shortening the time taken between materials science & prototype development. In this project Electrosciences will develop a new measurement tool for inline quality assurance evaluation of the performance of novel piezoelectric polymers. These films are being considered for next generation 3D touch sensitive screens for mobile phones, tablets and other screen input device as well as higher sensitivity ultrasonic imaging and hydrophone/sonar sensitivity applications. The innovation lies at the heart of the sensor and relates the charge developed by the smart film when it is excited by a mechanical stimulus provided by the sensor system. Digital calibration of the low cost device provides for highly accurate and reliable test and evaluation, enabling end users and reel to reel processors to save many hundreds of thousands of pounds in offline benchtop testing of their materials development cycle. Electrosciences Ltd will continue to develop other novel instrumentation as it builds its UK capabilities, and overseas markets.

The generation of small sizes of liquids in forms of jets or droplets has a significant impact on our daily life in many levels. When an electric field is applied to a liquid meniscus formed out of a nozzle, electric charges are accumulated on the liquid surface producing stress. This electrically-driven stress deforms the meniscus into a cone shape known as Taylor cone and due to the singularity at the apex, a fine jet, much smaller than the nozzle in size is produced (electrojetting). This jet then breaks up into droplets due to Rayleigh instability. Understanding the physical mechanisms of this phenomenon has been the focus of scientists and engineers due to its use in a variety of technical applications, such as electrospray mass spectrometry and electro-hydrodynamic printing. The collapse of cavities on free liquid surfaces is another interesting phenomenon, in which effects such as momentum focusing can lead to the production of diminutive droplets and aerosols. This phenomenon has been exploited in applications such as wastewater treatment, drug delivery in microfluidics, crop spraying and inkjet printing. While both phenomena described above produce small droplets, each one of these has limitations that prevent it from producing submicron droplets of complex fluids with high viscosity and density. Our proposal then aims to comprehensively study, for the first time, the behavior of both cavity collapse jetting and electrojetting to provide deep insights into the dynamics of the micro-droplets emerged when both phenomena are combined. This would then allow us to develop a novel printing technique based on the knowledge acquired throughout our study. We will also develop a predictive theoretical model for the droplet size and its speed based on the operation conditions and the physical properties of the liquids. The ultimate goal of the project is to use the proposed printing method to fabricate high performance piezoelectric devices as evidence of the applicability and the effectiveness of the technique. The current available droplets generation techniques can produce droplets comparable to the nozzle size. Small and thin nozzles are more prone to clogging and breaking and more difficult to manufacture. This has hindered the implementation of these technologies in a variety of applications, in which the high-resolution printing of highly particle-loaded inks (>5000 cP) is required. This project aims to solve this problem by proposing a novel technique that capable of printing highly viscous functional materials with small sizes (< 1 micron), surpassing the range of sizes and materials offered by the current printing systems in the market. A preliminary data shows that the new technique can produce jets that are up to 100 times smaller than the nozzle in size (no need for small nozzles) and printing frequency that is one order of magnitude higher than the traditional natural electrojetting pulsation technique (fast printing). The proposed system offers also a solution to the problem of electrojetting on non-conductive surfaces. Depositing subsequent charged drops with the same polarity on nonconductive surfaces is problematic because this creates a repulsion force between the droplets leading to splashing and hence poor printing. This is because the nonconductive surface does not permit the charges within the drops to dissipate. However, the flexibility of the proposed system could allow us to neutralize the charges of the subsequent droplets, which will solve the problem and ensure high-resolution printing even on non-conductive surfaces. This will push forward the implementation on applications such as high-resolution printed electronics, manufacturing microlenses by depositing liquid crystals micro/nano droplets and many other applications that depends on printing complex fluids and active materials with high resolution such as additive manufacturing of tissues and organs.