Let There Be Light: Photo-Induced Reaction Synthesis—Advancing Manufacturing Horizons

Photo-induced reactions, also known as photochemical reactions, are chemical processes that are initiated or driven by the absorption of light energy. Photo-induced reactions have been applied in a variety of fields from organic synthesis to polymer curation. One such application of much current interest is additive manufacturing (AM)—a technique used within a variety of fields to produce intricately shaped components. Currently, additive manufacturing is utilized within the solar, medicine, electronic, and nuclear application industries, making it a diverse and expansive system of production. Present reviewed AM production methods include laser powder bed fusion (L-PBF), stereolithography (SLA), direct energy deposition (DED), and selective laser sintering (SLS). However, the literature points to the need for expansion of feedstock capabilities as the horizon broadens to extreme environments like nuclear reactors, a solution which might be found in photolytic reaction synthesis. This review examines photo-induced synthesis most applicable to additive manufacturing, focusing on four key reaction types: oxidation–reduction, combustion, decomposition and polymerization. Past and present applications, future challenges, and emerging opportunities regarding photolytic reaction synthesis are analyzed. This assessment provides insights into the current state and future potential of these reactions in advancing additive manufacturing technologies.