Industries creating inorganic, organic, and agricultural chemicals use a staggering 4.2% of the worldwide delivered energy, mainly from unsustainable fossil fuels. Meanwhile, the sun provides energy that could be utilized to power photochemical reactions sustainably and cleanly. Recent advances revealing how localized surface plasmon resonances (LSPRs), light-driven electron oscillations in metal nanoparticles, can concentrate light at the molecular scale made the dream of efficient photochemistry one step closer. However, plasmonic materials are almost exclusively constructed from the rare and unsustainable metals Ag and Au. In addition to being incompatible with current industrial practices relying on catalytic surfaces to lower energy barriers and guide reactions, Ag and Au cause prohibitive cost challenges for real-world applications. But there is hope: several of the few metals predicted to sustain LSPRs and become potential alternatives to Ag and Au are amongst the most abundant, i.e. sustainable, elements on Earth (Al, Mg, Na, K). The way forward, and key objective of my proposal, is thus to design, synthesize, and understand multimetallic nanostructures where a cheap, Earth-abundant plasmonic material traps and concentrates (sun)light directly at a catalytic surface to efficiently and intelligently power and choreograph chemical reactions. To achieve this ambitious goal, I devised a project concurrently advancing important aspects of sustainable plasmon-enhanced catalysis, from the development of two synthetic approaches for Earth-abundant plasmonic-catalysts, to the fundamental studies of light-trapping in these new materials with state-of-the-art numerical and experimental approaches and the unravelling of the relative contribution of plasmon-generated hot electrons, enhanced field, and heat using key model chemical reactions. These results will help develop a more sustainable future by lowering our reliance on both fossil fuels and rare metals.