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1. Isotope Effect in Bilayer WSe ₂

   https://doi.org/10.1021/acs.nanolett.8b04269  

   Wu, Wei; Morales-Acosta, Mayra Daniela; Wang, Yongqiang; Pettes, Michael Thompson (February 2019, Nano Letters)
2. Revised microbial and photochemical triple-oxygen isotope effects improve marine gross oxygen production estimates

   https://doi.org/10.1093/pnasnexus/pgac233  

   Sutherland, Kevin M.; Johnston, David T.; Hemingway, Jordon D.; Wankel, Scott D.; Ward, Collin P.; Haas, ed., Charles (October 2022, PNAS Nexus)

   Abstract The biogeochemical fluxes that cycle oxygen (O2) play a critical role in regulating Earth’s climate and habitability. Triple-oxygen isotope (TOI) compositions of marine dissolved O2 are considered a robust tool for tracing oxygen cycling and quantifying gross photosynthetic O2 production. This method assumes that photosynthesis, microbial respiration, and gas exchange with the atmosphere are the primary influences on dissolved O2 content, and that they have predictable, fixed isotope effects. Despite its widespread use, there are major elements of this approach that remain uncharacterized, including the TOI dynamics of respiration by marine heterotrophic bacteria and abiotic O2 sinks such as the photochemical oxidation of dissolved organic carbon (DOC). Here, we report the TOI fractionation for O2 utilization by two model marine heterotrophs and by abiotic photo-oxidation of representative terrestrial and coastal marine DOC. We demonstrate that TOI slopes associated with these processes span a significant range of the mass-dependent domain (λ = 0.499 to 0.521). A sensitivity analysis reveals that even under moderate productivity and photo-oxidation scenarios, true gross oxygen production may deviate from previous estimates by more than 20% in either direction. By considering a broader suite of oxygen cycle reactions, our findings challenge current gross oxygen production estimates and highlight several paths forward to better understanding the marine oxygen and carbon cycles. 

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3. Plasmonic Nickel–TiO ₂ Heterostructures for Visible‐Light‐Driven Photochemical Reactions

   https://doi.org/10.1002/anie.201901987  

   He, Shuai; Huang, Jiawei; Goodsell, Justin L.; Angerhofer, Alexander; Wei, Wei David (March 2019, Angewandte Chemie International Edition)

   Abstract Plasmon‐mediated carrier transfer (PMCT) at metal–semiconductor heterojunctions has been extensively exploited to drive photochemical reactions, offering intriguing opportunities for solar photocatalysis. However, to date, most studies have been conducted using noble metals. Inexpensive materials capable of generating and transferring hot carriers for photocatalysis via PMCT have been rarely explored. Here, we demonstrate that the plasmon excitation of nickel induces the transfer of both hot electrons and holes from Ni to TiO₂in a rationally designed Ni–TiO₂heterostructure. Furthermore, it is discovered that the transferred hot electrons either occupy oxygen vacancies (V_O) or produce Ti³⁺on TiO₂, while the transferred hot holes are located on surface oxygens at TiO₂. Moreover, the transferred hot electrons are identified to play a primary role in driving the degradation of methylene blue (MB). Taken together, our results validate Ni as a promising low‐cost plasmonic material for prompting visible‐light photochemical reactions. 

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4. Photochemical Fluorination of TiO ₂ (110) Produces an Atomically Thin Passivating Layer

   https://doi.org/10.1021/acs.jpcc.2c00651  

   DeBenedetti, William J.; Hines, Melissa A. (March 2022, The Journal of Physical Chemistry C)
5. Photochemical H ₂ Evolution from Bis(diphosphine)nickel Hydrides Enables Low-Overpotential Electrocatalysis

   https://doi.org/10.1021/jacs.1c10628  

   Stratakes, Bethany M.; Wells, Kaylee A.; Kurtz, Daniel A.; Castellano, Felix N.; Miller, Alexander J. (December 2021, Journal of the American Chemical Society)