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1. The effects of methanol clustering on methanol–water nucleation

   https://doi.org/10.1063/5.0120876  

   Sun, Tong; Wilemski, Gerald; Hale, Barbara N.; Wyslouzil, Barbara E. (November 2022, The Journal of Chemical Physics)

   The formation of subcritical methanol clusters in the vapor phase is known to complicate the analysis of nucleation measurements. Here, we investigate how this process affects the onset of binary nucleation as dilute water–methanol mixtures in nitrogen carrier gas expand in a supersonic nozzle. These are the first reported data for water–methanol nucleation in an expansion device. We start by extending an older monomer–dimer–tetramer equilibrium model to include larger clusters, relying on Helmholtz free energy differences derived from Monte Carlo simulations. The model is validated against the pressure/temperature measurements of Laksmono et al. [Phys. Chem. Chem. Phys. 13, 5855 (2011)] for dilute methanol–nitrogen mixtures expanding in a supersonic flow prior to the appearance of liquid droplets. These data are well fit when the maximum cluster size imax is 6–12. The extended equilibrium model is then used to analyze the current data. On the addition of small amounts of water, heat release prior to particle formation is essentially unchanged from that for pure methanol, but liquid formation proceeds at much higher temperatures. Once water comprises more than ∼24 mol % of the condensable vapor, droplet formation begins at temperatures too high for heat release from subcritical cluster formation to perturb the flow. Comparing the experimental results to binary nucleation theory is challenged by the need to extrapolate data to the subcooled region and by the inapplicability of explicit cluster models that require a minimum of 12 molecules in the critical cluster. 

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2. Methanol tolerance of atomically dispersed single metal site catalysts: mechanistic understanding and high-performance direct methanol fuel cells

   https://doi.org/10.1039/d0ee01968b  

   Shi, Qiurong; He, Yanghua; Bai, Xiaowan; Wang, Maoyu; Cullen, David A.; Lucero, Macros; Zhao, Xunhua; More, Karren L.; Zhou, Hua; Feng, Zhenxing; et al (January 2020, Energy & Environmental Science)

   Proton-exchange membrane fuel cells (PEMFCs) and direct methanol fuel cells (DMFCs) are promising power sources from portable electronic devices to vehicles. The high-cost issue of these low-temperature fuel cells can be primarily addressed by using platinum-group metal (PGM)-free oxygen reduction reaction (ORR) catalysts, in particular atomically dispersed metal–nitrogen–carbon (M–N–C, M = Fe, Co, Mn). Furthermore, a significant advantage of M–N–C catalysts is their superior methanol tolerance over Pt, which can mitigate the methanol cross-over effect and offer great potential of using a higher concentration of methanol in DMFCs. Here, we investigated the ORR catalytic properties of M–N–C catalysts in methanol-containing acidic electrolytes via experiments and density functional theory (DFT) calculations. FeN 4 sites demonstrated the highest methanol tolerance ability when compared to metal-free pyridinic N, CoN 4 , and MnN 4 active sites. The methanol adsorption on MN 4 sites is even strengthened when electrode potentials are applied during the ORR. The negative influence of methanol adsorption becomes significant for methanol concentrations higher than 2.0 M. However, the methanol adsorption does not affect the 4e − ORR pathway or chemically destroy the FeN 4 sites. The understanding of the methanol-induced ORR activity loss guides the design of promising M–N–C cathode catalyst in DMFCs. Accordingly, we developed a dual-metal site Fe/Co–N–C catalyst through a combined chemical-doping and adsorption strategy. Instead of generating a possible synergistic effect, the introduced Co atoms in the first doping step act as “scissors” for Zn removal in metal–organic frameworks (MOFs), which is crucial for modifying the porosity of the catalyst and providing more defects for stabilizing the active FeN 4 sites generated in the second adsorption step. The Fe/Co–N–C catalyst significantly improved the ORR catalytic activity and delivered remarkably enhanced peak power densities ( i.e. , 502 and 135 mW cm −2 ) under H 2 –air and methanol–air conditions, respectively, representing the best performance for both types of fuel cells. Notably, the fundamental understanding of methanol tolerance, along with the encouraging DMFC performance, will open an avenue for the potential application of atomically dispersed M–N–C catalysts in other direct alcohol or ammonia fuel cells. 

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3. Domino electroreduction of CO2 to methanol on a molecular catalyst

   https://doi.org/10.1038/s41586-019-1760-8  

   Wu, Yueshen; Jiang, Zhan; Lu, Xu; Liang, Yongye; Wang, Hailiang (November 2019, Nature)
4. Mechanism-guided realization of selective carbon monoxide electroreduction to methanol

   https://doi.org/10.1038/s44160-023-00384-6  

   Li, Jing; Shang, Bo; Gao, Yuanzuo; Cheon, Seonjeong; Rooney, Conor L; Wang, Hailiang (December 2023, Nature Synthesis)
5. Crystal structure of 1 H -imidazole-1-methanol

   https://doi.org/10.1107/S2056989022002614  

   Wysocki, Megan M.; Puzovic, Gorana; Dowell, Keith L.; Reinheimer, Eric W.; Gerlach, Deidra L. (April 2022, Acta Crystallographica Section E Crystallographic Communications)

   The synthesis and the crystal structure of 1 H -imidazole-1-methanol, C 4 H 6 N 2 O, are described. This compound comprises an imidazole ring with a methanol group attached at the 1-position affording an imine nitrogen atom able to receive a hydrogen bond and an alcohol group able to donate to a hydrogen bond. This imidazole methanol crystallizes with monoclinic ( P 2 1 / n ) symmetry with three symmetry-unique molecules. These three molecules are connected via O—H...N hydrogen bonding in a head-to-tail configuration to form independent three-membered macrocycles. 

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