FMSG: Bio: Interface-Directed Manufacturing of Piezoelectric Biocrystal Thin Films

Environmental stewardship and sustainability are major considerations for future manufacturing. Renewable, biocompatible, degradable, and nature-derived biomaterials are beginning to show great promise in a wide range of energy- and electronics-related areas. Among many material candidates, amino acids, the most basic building blocks of life, have shown intriguing properties which could make them suitable for application in semiconductor devices, energy conversion, and sustainable electronics. To realize these promises, new methods are needed to enable continuous growth of amino acid films in a manufacturing-ready system. A recent breakthrough by the team suggests that high-quality amino acid biocrystal films may be continuously produced when guided by a special interface between a polymer and a water solution. Therefore, this Future Manufacturing Seed Grant (FMSG) project seeks fundamental understanding of the interactions of the mixed materials in order to understand what controls the polymer-water interfaces in a continuous polymer extrusion system, and how the mixture in turn controls amino acid crystal formation and its properties. Knowledge obtained from this project may be transformative to the manufacturing of biocrystal thin films from amino acids and their derivatives and allow creation of structures which are otherwise unachievable by existing manufacturing techniques. Discoveries and innovations from this project will catalyze a new interface-guided manufacturing technique for biocrystal thin films, enabling a novel material paradigm for eco-friendly and biocompatible electronics and energy devices. The objective of this project is to obtain fundamental knowledge that enables transition from a static interface-guided crystallization of amino acids to a dynamic and continuous precipitation process in a manufacturing-ready system. To achieve this objective, the team will develop a new apparatus for continuously producing polymer-water bi-phase films. Experimental and computational methods will be combined to understand and predict the dynamic conditions of the water-polymer system during continuous cooling. These conditions will be used to study the continuous crystallization kinetics of amino acid crystals and explain the role of the water-polymer interface as a key controlling factor. In addition, the piezoelectric properties of amino acid crystal films, which allow conversion of mechanical energy into electricity, will be quantified as a benchmark for film quality evaluation. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.