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  1. Free, publicly-accessible full text available August 17, 2024
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  3. The addition of research-focused experiences to undergraduate chemistry laboratory courses has been shown to bolster student learning, enhance student retention in STEM, and improve student self-identity as scientists. In the area of synthetic organic chemistry, the preparation of libraries of compounds with novel optical and electronic properties can provide a natural motivational goal for research-focused exercises that can be undertaken by individual students or collectively as a class. However, integrating such experiences into a community college teaching laboratory setting can face challenges imposed by the cost of supplies, limited laboratory space, and access to characterization facilities. To address these challenges, we have devised a sequence of inquiry-driven, research-focused laboratory exercises that can be readily integrated into an organic chemistry laboratory course with minimal cost. This sequence consists of a multistep synthesis of perylenediimide dyes that introduces students to advanced synthetic techniques, such as organometallic coupling reactions, column purification, and reactions performed under inert atmosphere. This high-yield, three-part synthesis can be easily varied by individual students or small groups within a class to form a broad library of compounds with potential utility for applications in light harvesting, molecular electronics, catalysis, and medicine. We describe the design of low-cost workstations for chemical synthesis under inert atmosphere and provide auxiliary lesson plans that can be used to expand the scope of a laboratory course beyond synthetic organic chemistry by introducing students to concepts in molecular spectroscopy. 
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  4. Solvated electrons are powerful reducing agents capable of driving some of the most energetically expensive reduction reactions. Their generation under mild and sustainable conditions remains challenging though. Using near-ultraviolet irradiation under low-intensity one-photon conditions coupled with electrochemical and optical detection, we show that the yield of solvated electrons in water is increased more than 10 times for nanoparticle-decorated electrodes compared to smooth silver electrodes. Based on the simulations of electric fields and hot carrier distributions, we determine that hot electrons generated by plasmons are injected into water to form solvated electrons. Both yield enhancement and hot carrier production spectrally follow the plasmonic near-field. The ability to enhance solvated electron yields in a controlled manner by tailoring nanoparticle plasmons opens up a promising strategy for exploiting solvated electrons in chemical reactions. 
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  5. Here, films using CdSe nanocrystal (NC) triplet photosensitizers in conjunction with diphenylanthracene (DPA) emitters were assembled to address several challenges to practical applications for solution-based photon upconversion. By using poly(9-vinylcarbazole) as a phosphorescent host in this film, volatile organic solvents are eliminated, the spontaneous crystallization of the emitter is significantly retarded, and ∼1.5% photon upconversion quantum yield (out of a maximum of 50%) is obtained. Transient absorption spectroscopy on nanosecond-to-microsecond time scales reveals this efficiency is enabled by an exceptionally long triplet lifetime of 3.4 ± 0.3 ms. Ultimately, we find the upconversion efficiency is limited by incomplete triplet–triplet annihilation, which occurs with a rate 3–4 orders of magnitude slower than in solution-phase upconversion systems. 
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