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1. The Potential of Zero Total Charge Predicts Cation Effects for the Oxygen Reduction Reaction

   https://doi.org/10.1021/acsenergylett.4c01897  

   Bender, Jay T; Sanspeur, Rohan Yuri; Valles, Angel E; Uvodich, Alyssa K; Milliron, Delia J; Kitchin, John R; Resasco, Joaquin (September 2024, ACS Energy Letters)
2. Quantifying the ultrafast and steady-state molecular reduction potential of a plasmonic photocatalyst

   https://doi.org/10.1073/pnas.2305932120  

   Warkentin, Christopher L.; Frontiera, Renee R. (October 2023, Proceedings of the National Academy of Sciences)

   Plasmonic materials are promising photocatalysts as they are well suited to convert light into hot carriers and heat. Hot electron transfer is suggested as the driving force in many plasmon-driven reactions. However, to date, there are no direct molecular measures of the rate and yield of plasmon-to-molecule electron transfer or energy of these electrons on the timescale of plasmon decay. Here, we use ultrafast and spectroelectrochemical surface-enhanced Raman spectroscopy to quantify electron transfer from a plasmonic substrate to adsorbed methyl viologen molecules. We observe a reduction yield of 2.4 to 3.5% on the picosecond timescale, with plasmon-induced potentials ranging from $-$3.1 to $-$4.5 mV. Excitingly, some of these reduced species are stabilized and persist for tens of minutes. This work provides concrete metrics toward optimizing material–molecule interactions for efficient plasmon-driven photocatalysis. 

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3. Plasma parameters and the reduction potential at a plasma–liquid interface

   https://doi.org/10.1039/d2cp00203e  

   Oldham, Trey; Yatom, Shurik; Thimsen, Elijah (June 2022, Physical Chemistry Chemical Physics)

   Nonthermal plasmas in contact with liquids have been shown to generate a variety of reactive species capable of initiating reduction–oxidation (redox) reactions at the electrochemically active plasma–liquid interface. In conventional electrochemical cells, selective redox chemistry is achieved by controlling the reduction potential at the solid electrode–electrolyte interface by applying a bias via an external circuit. In the case of plasma–liquid systems, an analogous means of tuning the reduction potential near the interface has not clearly been identified. When treated as a floating surface, the liquid is expected to adopt a net negative charge to balance the flux of hot electrons and relatively cold positive ions. The reduction potential near the plasma–liquid interface is hypothesized to be proportional to the floating potential, which can be approximated using an analytical model provided the plasma parameters are known. Herein, we present a framework for correlating the electron density and electron temperature of a noble gas plasma jet to the reduction potential near the plasma–liquid interface. The plasma parameters were acquired for an argon atmospheric plasma jet in contact with an aqueous solution by means of laser Thomson scattering. The reduction potential was determined using identical reference electrodes to measure the potential difference between the plasma–liquid interface and bulk solution. Interestingly, the measured reduction potentials near the plasma–liquid interface were found to be in good agreement with the model-predicted values determined using the plasma parameters obtained from the Thomson scattering experiments. 

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4. Redox-inactive metals modulate the reduction potential in heterometallic manganese–oxido clusters

   https://doi.org/10.1038/nchem.1578  

   Tsui, Emily Y.; Tran, Rosalie; Yano, Junko; Agapie, Theodor (April 2013, Nature Chemistry)
5. Investigating the Potential Drag Reduction and Thermal Transport Improvement in Textured Microchannels

   https://doi.org/10.1115/FEDSM2021-65760  

   Rabiei, Nastaran; McDonough, Grace; Hidrovo, Carlos H. (January 2021, ASME 2021 Fluids Engineering Division Summer Meeting)

   Abstract Over the past few decades, microscale duct flow has been the key element for many applications, such as drug delivery and microelectronics cooling. To enhance the performance of such systems and to save more energy, looking for new ways to control the hydrodynamic and thermal characteristics of the microchannel flow has been of great interest lately. The aim of this research is to gain a better understanding of the flow physics within microchannels with microtextured walls. Therefore, a set of numerical study has been conducted on the combined effect of flow and heat transfer for spanwise rectangular trenches. The surface microstructures increase the wetting surface area, which is supposed to increase friction (skin drag). Recirculation produced inside the grooves, on the other hand, aids in increasing main flow slippage and lowering pressure drop along the microchannel. It is also worth noting that recirculation creates a negative pressure difference in the opposite direction of the flow (pressure drag). The geometrical parameters of the trenches have a significant impact on the trade-off between the drag reducing and drag increasing factors in textured microchannel flow, which is addressed in this research. Furthermore, the textures disrupt the thermal boundary layer, which can boost thermal transport through recirculation mixing. However, the stagnant fluid trapped within the grooves has weak convective heat transfer. So far, the results have been promising and a drag reduction of about 25% has been reported for wide trenches at low Reynolds numbers. Thermal transport enhancement is also possible for some tested geometries when the flow has not achieved the thermally fully development. 

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