ACS Physical Chemistry Au最新文献

{"title":"Heavy Solution for Molecular Thermal Management: Phonon Transport Suppression with Heavy Atoms","authors":"William Bro-Jørgensen,&nbsp;Andreas Juul Bay-Smidt,&nbsp;Davide Donadio and Gemma C. Solomon*,&nbsp;","doi":"10.1021/acsphyschemau.4c0008410.1021/acsphyschemau.4c00084","DOIUrl":"https://doi.org/10.1021/acsphyschemau.4c00084https://doi.org/10.1021/acsphyschemau.4c00084","url":null,"abstract":"<p >Thermal management in molecular systems presents challenges that require a deeper understanding of phonon transport, an essential aspect of heat conduction in single-molecule junctions. Our work introduces the use of heavy atoms as a strategy for suppressing phonon transport in organic molecules. Starting with a one-dimensional (1D) force-constant model and density functional theory calculations of model chemical systems, we illustrate how increasing the mass of a central atom affects phonon transmission and conductance. Following this, we turned our attention to the chemically accessible systems of metallapolyynes and extended metal atom chains (EMACs). Our findings suggest that several of the studied EMACs exhibit thermal conductance either near or below a recently proposed threshold of 10 pW/K─a crucial step toward reaching high thermoelectric figure of merits. Specifically, we predict that the molecule MoMoNi(npo)₄(NCS)₂ has a thermal conductance of just 8.3 pW/K at 300 K. Our results demonstrate that conceptually simple chemical modifications can markedly reduce the thermal conductance of single molecules; these results both deepen our understanding of the mechanisms driving single-molecule phonon thermal conductance and suggest a path toward using single molecules as thermoelectric materials.</p>","PeriodicalId":29796,"journal":{"name":"ACS Physical Chemistry Au","volume":"5 2","pages":"162–170 162–170"},"PeriodicalIF":3.7,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsphyschemau.4c00084","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143696461","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Heavy Solution for Molecular Thermal Management: Phonon Transport Suppression with Heavy Atoms.","authors":"William Bro-Jørgensen, Andreas Juul Bay-Smidt, Davide Donadio, Gemma C Solomon","doi":"10.1021/acsphyschemau.4c00084","DOIUrl":"10.1021/acsphyschemau.4c00084","url":null,"abstract":"<p><p>Thermal management in molecular systems presents challenges that require a deeper understanding of phonon transport, an essential aspect of heat conduction in single-molecule junctions. Our work introduces the use of heavy atoms as a strategy for suppressing phonon transport in organic molecules. Starting with a one-dimensional (1D) force-constant model and density functional theory calculations of model chemical systems, we illustrate how increasing the mass of a central atom affects phonon transmission and conductance. Following this, we turned our attention to the chemically accessible systems of metallapolyynes and extended metal atom chains (EMACs). Our findings suggest that several of the studied EMACs exhibit thermal conductance either near or below a recently proposed threshold of 10 pW/K-a crucial step toward reaching high thermoelectric figure of merits. Specifically, we predict that the molecule MoMoNi(npo)₄(NCS)₂ has a thermal conductance of just 8.3 pW/K at 300 K. Our results demonstrate that conceptually simple chemical modifications can markedly reduce the thermal conductance of single molecules; these results both deepen our understanding of the mechanisms driving single-molecule phonon thermal conductance and suggest a path toward using single molecules as thermoelectric materials.</p>","PeriodicalId":29796,"journal":{"name":"ACS Physical Chemistry Au","volume":"5 2","pages":"162-170"},"PeriodicalIF":3.7,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11950860/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143753835","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Understanding (La,Sr)(Co,Fe)O_3-δ Phase Instability within SOECs Using a Combined Experimental and Atomistic Modeling Approach.","authors":"Heather S Slomski, Jonas L Kaufman, Michael J Dzara, Nicholas A Strange, Cameron Priest, Jeremy L Hartvigsen, Nicholas Kane, Micah Casteel, Brandon C Wood, David S Ginley, Kyoung E Kweon, Brian P Gorman, Sarah Shulda","doi":"10.1021/acsphyschemau.4c00095","DOIUrl":"10.1021/acsphyschemau.4c00095","url":null,"abstract":"<p><p>Understanding the onset of degradation in the air electrode within solid oxide electrolysis cells (SOECs), and the subsequent impact on cell performance, is a critical step in mitigating the performance losses and stability issues of SOECs. In an effort to identify early onset degradation phenomena, SOECs were characterized as fabricated and after testing potentiostatically at 1.3 V for 1000 h at 750 °C. SOEC air electrodes composed of a 1:1 composite of La_0.6Sr_0.4Co_0.2Fe_0.8O_3-δ (6428-LSCF) and Gd_0.1Ce_0.9O_1.95 (GDC) were studied using synchrotron X-ray diffraction (XRD), scanning transmission electron microscopy coupled with energy dispersive X-ray spectroscopy (STEM-EDS), and X-ray absorption near-edge spectroscopy (XANES) to evaluate the changes in the air electrode structurally and chemically. These techniques show the migration of Sr species from the air electrode through pores in the GDC barrier layer, progressing to the electrolyte boundary, where it accumulates and reacts with (Zr_0.84Y_0.16)O_2-δ (YSZ) to form SrZrO₃. Microscopy results are paired with atomistic simulations to better understand the relationship between the thermodynamic instability of 6428-LSCF and cell fabrication/testing conditions. First-principles calculations reveal that LSCF-6428 is not stable during cell manufacturing and testing conditions, which supports the experimental identification of secondary phases in both as-fabricated and tested cells. Together, these results demonstrate that the challenging environments encountered by SOECs during cell manufacturing and operation lead to instabilities of the target 6428-LSCF anode material and underscore the need for more durable, high-performing SOEC components.</p>","PeriodicalId":29796,"journal":{"name":"ACS Physical Chemistry Au","volume":"5 2","pages":"207-218"},"PeriodicalIF":3.7,"publicationDate":"2025-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11950864/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143754585","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Understanding (La,Sr)(Co,Fe)O3−δ Phase Instability within SOECs Using a Combined Experimental and Atomistic Modeling Approach","authors":"Heather S. Slomski,&nbsp;Jonas L. Kaufman,&nbsp;Michael J. Dzara,&nbsp;Nicholas A. Strange,&nbsp;Cameron Priest,&nbsp;Jeremy L. Hartvigsen,&nbsp;Nicholas Kane,&nbsp;Micah Casteel,&nbsp;Brandon C. Wood,&nbsp;David S. Ginley,&nbsp;Kyoung E. Kweon*,&nbsp;Brian P. Gorman* and Sarah Shulda*,&nbsp;","doi":"10.1021/acsphyschemau.4c0009510.1021/acsphyschemau.4c00095","DOIUrl":"https://doi.org/10.1021/acsphyschemau.4c00095https://doi.org/10.1021/acsphyschemau.4c00095","url":null,"abstract":"<p >Understanding the onset of degradation in the air electrode within solid oxide electrolysis cells (SOECs), and the subsequent impact on cell performance, is a critical step in mitigating the performance losses and stability issues of SOECs. In an effort to identify early onset degradation phenomena, SOECs were characterized as fabricated and after testing potentiostatically at 1.3 V for 1000 h at 750 °C. SOEC air electrodes composed of a 1:1 composite of La_0.6Sr_0.4Co_0.2Fe_0.8O_3−δ (6428-LSCF) and Gd_0.1Ce_0.9O_1.95 (GDC) were studied using synchrotron X-ray diffraction (XRD), scanning transmission electron microscopy coupled with energy dispersive X-ray spectroscopy (STEM-EDS), and X-ray absorption near-edge spectroscopy (XANES) to evaluate the changes in the air electrode structurally and chemically. These techniques show the migration of Sr species from the air electrode through pores in the GDC barrier layer, progressing to the electrolyte boundary, where it accumulates and reacts with (Zr_0.84Y_0.16)O_2−δ (YSZ) to form SrZrO₃. Microscopy results are paired with atomistic simulations to better understand the relationship between the thermodynamic instability of 6428-LSCF and cell fabrication/testing conditions. First-principles calculations reveal that LSCF-6428 is not stable during cell manufacturing and testing conditions, which supports the experimental identification of secondary phases in both as-fabricated and tested cells. Together, these results demonstrate that the challenging environments encountered by SOECs during cell manufacturing and operation lead to instabilities of the target 6428-LSCF anode material and underscore the need for more durable, high-performing SOEC components.</p>","PeriodicalId":29796,"journal":{"name":"ACS Physical Chemistry Au","volume":"5 2","pages":"207–218 207–218"},"PeriodicalIF":3.7,"publicationDate":"2025-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsphyschemau.4c00095","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143696423","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Improved Skill of Rotaxanes to Recognize Cations: A Theoretical Perspective","authors":"Renato Pereira Orenha*,&nbsp;Alvaro Muñoz-Castro,&nbsp;Maurício Jeomar Piotrowski,&nbsp;Giovanni F. Caramori*,&nbsp;Renato Gonçalves Rocha and Renato Luis Tame Parreira*,&nbsp;","doi":"10.1021/acsphyschemau.4c0009010.1021/acsphyschemau.4c00090","DOIUrl":"https://doi.org/10.1021/acsphyschemau.4c00090https://doi.org/10.1021/acsphyschemau.4c00090","url":null,"abstract":"<p >Cations have significant applications in fields such as medicinal inorganic chemistry and catalysis. Rotaxanes are composed of a macrocyclic structure that is mechanically interlocked with a linear molecule. These mechanically interlocked molecules (MIMs) provide a potential chemical environment that allows for the interaction with cations. In this study, the bonding situations between rotaxanes or their acyclic/cyclic molecular derivatives and: (i) transition metal (Zn²⁺ and Cd²⁺); or (ii) alkali metal (Li⁺, Na⁺, and K⁺), cations have been studied. It is notable that among the MIMs structures, the rotaxanes demonstrate enhanced interactions with cations in comparison to the cyclic and, notably, the acyclic derivative molecules. The modification of rotaxane structures through structural changes and chemical reduction represents an intriguing approach to enhance cationic recognition, which is supported by the formation of more favorable electrostatic and/or orbital interaction energies in comparison with Pauli repulsive energies. The findings of this investigation can be employed in the synthesis of compounds with enhanced cation recognition capabilities.</p>","PeriodicalId":29796,"journal":{"name":"ACS Physical Chemistry Au","volume":"5 2","pages":"183–194 183–194"},"PeriodicalIF":3.7,"publicationDate":"2025-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsphyschemau.4c00090","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143696465","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Improved Skill of Rotaxanes to Recognize Cations: A Theoretical Perspective.","authors":"Renato Pereira Orenha, Alvaro Muñoz-Castro, Maurício Jeomar Piotrowski, Giovanni F Caramori, Renato Gonçalves Rocha, Renato Luis Tame Parreira","doi":"10.1021/acsphyschemau.4c00090","DOIUrl":"10.1021/acsphyschemau.4c00090","url":null,"abstract":"<p><p>Cations have significant applications in fields such as medicinal inorganic chemistry and catalysis. Rotaxanes are composed of a macrocyclic structure that is mechanically interlocked with a linear molecule. These mechanically interlocked molecules (MIMs) provide a potential chemical environment that allows for the interaction with cations. In this study, the bonding situations between rotaxanes or their acyclic/cyclic molecular derivatives and: (i) transition metal (Zn²⁺ and Cd²⁺); or (ii) alkali metal (Li⁺, Na⁺, and K⁺), cations have been studied. It is notable that among the MIMs structures, the rotaxanes demonstrate enhanced interactions with cations in comparison to the cyclic and, notably, the acyclic derivative molecules. The modification of rotaxane structures through structural changes and chemical reduction represents an intriguing approach to enhance cationic recognition, which is supported by the formation of more favorable electrostatic and/or orbital interaction energies in comparison with Pauli repulsive energies. The findings of this investigation can be employed in the synthesis of compounds with enhanced cation recognition capabilities.</p>","PeriodicalId":29796,"journal":{"name":"ACS Physical Chemistry Au","volume":"5 2","pages":"183-194"},"PeriodicalIF":3.7,"publicationDate":"2025-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11950869/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143754554","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Is the Future of Materials Amorphous? Challenges and Opportunities in Simulations of Amorphous Materials","authors":"Ata Madanchi,&nbsp;Emna Azek,&nbsp;Karim Zongo,&nbsp;Laurent K. Béland,&nbsp;Normand Mousseau and Lena Simine*,&nbsp;","doi":"10.1021/acsphyschemau.4c0006310.1021/acsphyschemau.4c00063","DOIUrl":"https://doi.org/10.1021/acsphyschemau.4c00063https://doi.org/10.1021/acsphyschemau.4c00063","url":null,"abstract":"<p >Amorphous solids form an enormous and underutilized class of materials. In order to drive the discovery of new useful amorphous materials further we need to achieve a closer convergence between computational and experimental methods. In this review, we highlight some of the important gaps between computational simulations and experiments, discuss popular state-of-the-art computational techniques such as the Activation Relaxation Technique <i>nouveau</i> (ARTn) and Reverse Monte Carlo (RMC), and introduce more recent advances: machine learning interatomic potentials (MLIPs) and generative machine learning for simulations of amorphous matter (e.g., MAP). Examples are drawn from amorphous silicon and silica literature as well as from molecular glasses. Our outlook stresses the need for new computational methods to extend the time- and length-scales accessible through numerical simulations.</p>","PeriodicalId":29796,"journal":{"name":"ACS Physical Chemistry Au","volume":"5 1","pages":"3–16 3–16"},"PeriodicalIF":3.7,"publicationDate":"2024-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsphyschemau.4c00063","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143086803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Is the Future of Materials Amorphous? Challenges and Opportunities in Simulations of Amorphous Materials.","authors":"Ata Madanchi, Emna Azek, Karim Zongo, Laurent K Béland, Normand Mousseau, Lena Simine","doi":"10.1021/acsphyschemau.4c00063","DOIUrl":"10.1021/acsphyschemau.4c00063","url":null,"abstract":"<p><p>Amorphous solids form an enormous and underutilized class of materials. In order to drive the discovery of new useful amorphous materials further we need to achieve a closer convergence between computational and experimental methods. In this review, we highlight some of the important gaps between computational simulations and experiments, discuss popular state-of-the-art computational techniques such as the Activation Relaxation Technique <i>nouveau</i> (ARTn) and Reverse Monte Carlo (RMC), and introduce more recent advances: machine learning interatomic potentials (MLIPs) and generative machine learning for simulations of amorphous matter (e.g., MAP). Examples are drawn from amorphous silicon and silica literature as well as from molecular glasses. Our outlook stresses the need for new computational methods to extend the time- and length-scales accessible through numerical simulations.</p>","PeriodicalId":29796,"journal":{"name":"ACS Physical Chemistry Au","volume":"5 1","pages":"3-16"},"PeriodicalIF":3.7,"publicationDate":"2024-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11758375/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143047882","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design Criteria for Active and Selective Catalysts in the Nitrogen Oxidation Reaction","authors":"Muhammad Usama,&nbsp;Samad Razzaq and Kai S. Exner*,&nbsp;","doi":"10.1021/acsphyschemau.4c0005810.1021/acsphyschemau.4c00058","DOIUrl":"https://doi.org/10.1021/acsphyschemau.4c00058https://doi.org/10.1021/acsphyschemau.4c00058","url":null,"abstract":"<p >The direct conversion of dinitrogen to nitrate is a dream reaction to combine the Haber–Bosch and Ostwald processes as well as steam reforming using electrochemistry in a single process. Regrettably, the corresponding nitrogen oxidation (NOR) reaction is hampered by a selectivity problem, since the oxygen evolution reaction (OER) is both thermodynamically and kinetically favored in the same potential range. This opens the search for the identification of active and selective NOR catalysts to enable nitrate production under anodic reaction conditions. While theoretical considerations using the computational hydrogen electrode approach have helped in identifying potential material motifs for electrocatalytic reactions over the last decades, the inherent complexity of the NOR, which consists of ten proton-coupled electron transfer steps and thus at least nine intermediate states, poses a challenge for electronic structure theory calculations in the realm of materials screening. To this end, we present a different strategy to capture the competing NOR and OER at the atomic scale. Using a data-driven method, we provide a framework to derive generalized design criteria for materials with selectivity toward NOR. This leads to a significant reduction of the computational costs, since only two free-energy changes need to be evaluated to draw a first conclusion on NOR selectivity.</p>","PeriodicalId":29796,"journal":{"name":"ACS Physical Chemistry Au","volume":"5 1","pages":"38–46 38–46"},"PeriodicalIF":3.7,"publicationDate":"2024-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsphyschemau.4c00058","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143086486","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design Criteria for Active and Selective Catalysts in the Nitrogen Oxidation Reaction.","authors":"Muhammad Usama, Samad Razzaq, Kai S Exner","doi":"10.1021/acsphyschemau.4c00058","DOIUrl":"10.1021/acsphyschemau.4c00058","url":null,"abstract":"<p><p>The direct conversion of dinitrogen to nitrate is a dream reaction to combine the Haber-Bosch and Ostwald processes as well as steam reforming using electrochemistry in a single process. Regrettably, the corresponding nitrogen oxidation (NOR) reaction is hampered by a selectivity problem, since the oxygen evolution reaction (OER) is both thermodynamically and kinetically favored in the same potential range. This opens the search for the identification of active and selective NOR catalysts to enable nitrate production under anodic reaction conditions. While theoretical considerations using the computational hydrogen electrode approach have helped in identifying potential material motifs for electrocatalytic reactions over the last decades, the inherent complexity of the NOR, which consists of ten proton-coupled electron transfer steps and thus at least nine intermediate states, poses a challenge for electronic structure theory calculations in the realm of materials screening. To this end, we present a different strategy to capture the competing NOR and OER at the atomic scale. Using a data-driven method, we provide a framework to derive generalized design criteria for materials with selectivity toward NOR. This leads to a significant reduction of the computational costs, since only two free-energy changes need to be evaluated to draw a first conclusion on NOR selectivity.</p>","PeriodicalId":29796,"journal":{"name":"ACS Physical Chemistry Au","volume":"5 1","pages":"38-46"},"PeriodicalIF":3.7,"publicationDate":"2024-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11758373/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143047861","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}