The main objective of this EArly Concept Grant for Exploratory Research (EAGER) research project is to fabricate an artificial photosynthesis device that is capable of converting sunlight, CO2 and water into sugars for the production of biofuels. Solid freeform fabrication (SFF) enhanced by high-resolution heterogeneous printing technology will be investigated to design and build the innovative device with multi-layer interconnected channels and micro-porous structures. This research will enable manufacturing and deployment of large-scale solar conversion systems that not only mimic the nature process of photosynthesis for the production of biofuels, but also make these reactions independent of the life of nature plants. An interdisciplinary research team has been formed, synergistically combining the expertise of two investigators from Drexel University and Kansas State University in solid freeform fabrication, system design and control, biomaterials, biofuels and molecular biology. The U.S. government aims to replace 20 percent (51 billion gasoline-equivalent gallons) of fossil-based transportation fuels with biofuels by the year 2030. Producing this amount of biofuel would require an unsustainably large cropping area when using any bio-based sources (biomass) that are currently available. As an alternative technology, artificial photosynthesis can produce tremendous amounts of clean and renewable biofuels because of its extremely high solar conversion efficiency and carbon neutral nature. However, lacking commercially available artificial photosynthesis devices, there is a big gap between lab-scale artificial photosynthesis technologies and in-field applications. This project will research a new manufacturing system and method to first-time fabricate a leaf-tree-like artificial photosynthesis device. This research will be the first of its kind in solid freeform fabrication of artificial photosynthesis device integrated with polymers and protein/enzyme. Knowledge obtained from this study will guide design of structures and determination of manufacturing methods of the artificial photosynthesis device, which will eventually lead to large-scale use of commercially deployable constructs for biofuel manufacturing.
Successful completion of this research will lead to a new technology for designing and manufacturing an artificial photosynthesis device, which will help realize the vision of affordable bio-based energy manufacturing. Economically viable manufacturing of biofuels will greatly benefit the U.S. economy and energy security, as well as society and the environment in general. Success of the proposed activities will help expand the role of the manufacturing research community to create a new, trillion dollar energy manufacturing industry in the United States. Two doctoral students will be trained and three project-based learning modules will be created to strengthen the undergraduate engineering curricula, engaging students with design projects in design, manufacturing and energy engineering.
The main objective of this research is to fabricate an artificial photosynthesis device that is capable of converting sunlight, CO2 and water into glucose/sugars for the production of biofuels. Additive Manufacturing (AM) enhanced by high-resolution heterogeneous printing technology and multi-function nozzle array has been used to design and build the innovative device with multi-layer interconnected channels and micro-porous structures. Our proposed device has been heterogeneously printed using a specifically designed AM machine with multi-functional nozzle array. The first intellective merit is that we explored of a Multi-function, Multi-nozzle, and Multi-materials (3Multi) AM System for reaction layer printing: The unique AM system have the following features: (1) Multiple and exchangeable printing nozzles for different materials with wide range of viscosities; (2) Nozzle and reservoir heating to melt and keep the temperature for the printing materials; (3) Liquid nitrogen cooling for hydrogel material freezing; (4) Substrate heating for printed material fast solidification; (5) UV light curing or crosslinking for printed polymer solidification; (6) Heterogeneous materials structure printing; (7) High printing resolution (up to 10 μm line width); and (8) User-friendly interface and open system for easy modification. The second merit is that: Our work established a mathematical model for fluid behavior in pneumatic valve and relationship with fluid properties in additive manufacturing. The relationship can lead to a recipe for printing other 3D additive manufacturing materials in the future, that the input of fluid density, viscosity and surface tension automatically generates the G-code increment in Z direction, and the controller settings for valve, including but not limited to step time and feed rate percentage. The mathematical model provides a theoretical way to adjust the fluid by modifying the parameters of dispensing valve step time. The broad impacts in research aspects are: We have delivered several seminar locally to introduce our project developed technology and results. Based on this research we have published three conference papers, one journal paper, and three poster presentations. We have visited industrial partner nScript to discuss the collaboration progress. Our research have broad educational impact, including improved engagement and deepened understanding through project-based learning, strengthening of energy engineering, bio-fuels and materials science in the undergraduate curriculum, and enhancement of student recruitment. Our senior design teams have researched applications and challenges in energy engineering, and be encouraged to explore new ideas and methods of green energy production, and use AM technologies to design, construct, and test the artificial photosynthesis system to support the project. A new module has been developed for MEM438 Advanced Manufacturing Processes at Drexel, focusing on the manufacturing aspects of the multilayer and porous structures using AM and thin film coating. The experiments in this project require a lot of knowledge in additive manufacturing especially 3D printing machine, and chemistry and biology. This project involves 1 phd student from Drexel university, 1 phd student from North Carolina State University, and 2 undergraduate students, one from Drexel University, Department of Mechanical Engineering and Mechanics, and another from Department of Biomedical Engineering. The project provided training and experiment opportunities in both mechanical engineering and biology, especially handling chemicals and perform biology tests. The equipment used in the experiment including: In-house-made 3D printer, lyophilization machine, SEM (scanning electronic microscope), ABS plastic 3D printer, etc. Also the software used in this project including: Solidworks, AutoCAD, COMSOL, MATLAB, ImageJ, etc. This one year and then extended to second year exploratory project has laid down a solid foundation for photosynthesis process to generate biofuels. We have achieved significant intellective merits and broad impacts to the society through this funded project.
