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Non-invasive temperature probes have use in many settings where conventional thermometers may not be suitable or as efficient. An optical temperature probe is a material whose optical properties, such as photoluminescence (PL) or PL lifetime, are known as a function of temperature. We present results of PL lifetime studies of the organic dye Rhodamine B, which is a good candidate for use in temperature probes due to its large PL emission. We have measured PL lifetimes using time correlated single photon counting (TCSPC). The lifetimes were measured from temperatures of 15 K to 330 K. The lifetimes appear to be non-monotonic: they increase with temperature to a point, then decrease again. It is uncertain what is causing this unexpected trend, and we are in the process of verifying these lifetime measurements as well as studying other possible luminescent materials such as semiconductor quantum dots for application as temperature probes. *Research was performed at BYU as part of the NSF REU program, grant no. 1757998. 

Hydrogen (H2) gas is a possible alternate fuel to help meet increasing worldwide energy needs, but a major obstacle in the use of H2 for green, environmentally-friendly fuel is the energetic and chemical requirements to synthesize the gas. We are studying the use of photocatalytic reactions to produce H2, where a light-absorbing substance acts as a catalyst in shuttling electrons from a donor to protons that are reduced into H2. Previous research conducted at BYU showed that platinum nanoparticles bound to ferritin catalyzed the photoreaction of methyl viologen to reduce protons in an organic acid offered an increase in hydrogen production efficiency by up to 100 times over platinum black (a commonly available platinum-based catalyst). We are reporting on our efforts to optimize the synthesis of the platinum nanoparticles bound to ferritin that are used in this photocatalytic system and how we characterize these nanoparticles, as well as how these characteristics affect H2 production. *We'd like to thank the Brigham Young University Physics Department and the National Science Foundation (grant no. 1757998) for their generous funding. 

As energy needs grow ever greater in today's world, many scientists are investigating possible replacements for fossil fuels as an energy source. The use of hydrogen (H2) gas in particular is undergoing a significant amount of research, but a major obstacle in the use of H2 for green, environmentally-friendly fuel is the energetic and chemical requirement to synthesize the gas. A possibility in satisfying current and future H2 production needs is the use of photocatalytic reactions, where a light-absorbing substance acts as a catalyst in shuttling electrons from a donor to protons that are reduced into H2. Previous research conducted at BYU found such a system where platinum nanoparticles bound to ferritin catalyzed the photoreaction of methyl viologen to reduce protons in an organic acid, which offered a one hundred-fold increase in H2 production efficiency over photocatalytic reactions catalyzed by bulk platinum. We are reporting on our efforts to optimize the synthesis of the platinum nanoparticles bound to ferritin that are used in this photocatalytic system and how we characterize these nanoparticles. *We'd like to thank the Brigham Young University Physics Department and the National Science Foundation (grant no. 1757998) for their generous funding. To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2018.4CS.J03.3