The Journal of Physical Chemistry C最新文献

{"title":"Laser-Induced Emission Spectra of La0.95Nd0.05MnO3 Nanocrystals","authors":"João M. Gonçalves, Mariusz Stefanski, Robert Tomala, Agata Musialek, Bartłomiej Cichy, Marco Bettinelli, Wieslaw Strek","doi":"10.1021/acs.jpcc.4c07266","DOIUrl":"https://doi.org/10.1021/acs.jpcc.4c07266","url":null,"abstract":"The luminescence spectral properties of La_0.95Nd_0.05MnO₃ were investigated upon irradiation with a focused 808 nm CW (continuous wave) laser excitation. An anti-Stokes broadband emission in the visible range centered at 670 nm and a Stokes band in the infrared range centered around 2000 nm were recorded. Their intensities increased exponentially with excitation laser power. The mechanism of laser-induced emission is discussed in terms of an intervalence charge transfer mechanism involving the Mn³⁺–Mn⁴⁺ ionic pair.","PeriodicalId":61,"journal":{"name":"The Journal of Physical Chemistry C","volume":"53 1","pages":""},"PeriodicalIF":4.126,"publicationDate":"2025-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142981710","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Decoding the Interplay of Hydrogen Bonding, Dispersion, and Steric Interactions in Conformational Isomerism Among Functionalized Pillar[n]arenes","authors":"Ameevardhan Singh Patyal, Joshua D. Howe","doi":"10.1021/acs.jpcc.4c05974","DOIUrl":"https://doi.org/10.1021/acs.jpcc.4c05974","url":null,"abstract":"Pillar[<i>n</i>]arenes have garnered popularity due to their unique pillar-shaped structure, which results in hydrophobic cavities. These cavities facilitate the formation of inclusion complexes with guest molecules through noncovalent interactions such as π–π stacking, hydrogen bonding, and van der Waals interactions. Such host–guest interactions enable diverse functionalities in pillar[<i>n</i>]arenes, including molecule recognition, self-assembly, and encapsulation. Nevertheless, it is important to note that the host–guest properties of pillar[<i>n</i>]arenes can be influenced by conformational changes, primarily driven by the rotation of hydroquinone units about their methylene bridge axis. These structural changes can lead to variations in underlying noncovalent and steric interactions, impacting the overall stability of the host–guest system and potentially leading to selective uptake of guest molecules. Additionally, due to relative energy differences, we expect a distribution of pillar[<i>n</i>]arene conformations at thermal equilibrium. In this work, we employ density functional theory to evaluate ground-state electronic structures of pillar[<i>n</i>]arene conformations across pillar[<i>n</i>]arenes of various sizes and functionalizations. We have aimed to explore the impact of dispersion interactions, hydrogen bonding, and steric interactions on the overall energetics of pillar[<i>n</i>]arene conformations and determine the dominant conformation at 298 K using a Boltzmann-weighted distribution. The relative strengths of hydrogen bonds across various pillar[<i>n</i>]arene conformations have been examined using Bader’s quantum theory of atoms in molecules topological analysis. Furthermore, we also assessed the solvation of pillar[<i>n</i>]arenes in water using an implicit solvent model that unveils quantitative distinctions in hydrogen bonding and relative dispersion contributions among various pillar[<i>n</i>]arene conformations. Finally, pillar[<i>n</i>]arene conformations with more complex functional groups such as primary amine, alkyl bromide, and carboxylic acid have been studied to evaluate the interplay between underlying interactions such as hydrogen bonding, dispersion, and steric interactions and their collective impact on the structure and energetics of pillar[<i>n</i>]arene conformations.","PeriodicalId":61,"journal":{"name":"The Journal of Physical Chemistry C","volume":"36 1","pages":""},"PeriodicalIF":4.126,"publicationDate":"2025-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142981709","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular Simulation Study of Elasticity of Fluid-Saturated Zeolites","authors":"Santiago A. Flores Roman, Alina Emelianova, Gennady Y. Gor","doi":"10.1021/acs.jpcc.4c04839","DOIUrl":"https://doi.org/10.1021/acs.jpcc.4c04839","url":null,"abstract":"Zeolites are widely used for applications involving gas adsorption thanks to their crystalline porous structure, high surface area, and mechanical stability. Experiments using magnetoelastic sensors showed that gas adsorption can noticeably alter the elastic moduli of zeolites. Here, we utilized a combination of the classical molecular dynamics and Monte Carlo simulations to explore this effect in silico, calculating the bulk moduli of the zeolites, of the fluids adsorbed in these zeolites, and of the zeolite-fluid composites. We considered two gases─nitrogen and carbon dioxide, in two zeolite structures 13X and 4A. The moduli of the composite systems were calculated using two alternative approaches: from the moduli of the constituents (unsaturated zeolite and adsorbed fluid) using the Gassmann equation, and directly, using the Birch–Murnaghan equation of state. The direct approach showed better agreement with the experimental observations, raising a question on the applicability of the Gassmann equation for microporous zeolites.","PeriodicalId":61,"journal":{"name":"The Journal of Physical Chemistry C","volume":"7 1","pages":""},"PeriodicalIF":4.126,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142975576","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tritium Accommodation and Diffusion in Li8PbO6 from First-Principles Simulations","authors":"Andrew W. Davies, Samuel T. Murphy","doi":"10.1021/acs.jpcc.4c08016","DOIUrl":"https://doi.org/10.1021/acs.jpcc.4c08016","url":null,"abstract":"Li₈PbO₆ has been proposed as an alternative candidate breeding blanket material for use in fusion reactors. As lithium is burned inside the blanket, tritium is produced within the ceramic matrix until it reaches the surface, from where it is recovered by isotope exchange reactions. To fully understand the tritium recovery process, it is essential to understand how tritium is accommodated in the fuel and subsequently migrates to the surface. Therefore, in this work, we employ density functional theory (DFT) to examine tritium accommodation in Li₈PbO₆. We then used the nudged elastic band (NEB) method to understand the mechanisms for the migration of tritium-accommodating defects in Li₈PbO₆. We have found tritium is more likely bind to an oxygen ion and form a hydroxyl than exist in the traditional interstitial sites. We predict the barriers for migration of tritium interstitials to be anisotropic, with barriers of 0.27 and 0.69 eV along the <i>xy</i>-plane and through the <i>z</i>-axis, respectively. The barrier for escape from a lithium vacancy trapping site we found to be in the range of 0.76–0.85 eV, and an activation energy range of 0.67–1.18 eV for the migration of the trapping site as a whole. Due to the low migration energies found, we predict that aging of the blanket will have a lower significance on tritium release compared to other leading candidate materials.","PeriodicalId":61,"journal":{"name":"The Journal of Physical Chemistry C","volume":"43 1","pages":""},"PeriodicalIF":4.126,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142975601","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First-Principles Study on the Monomolecular Isomerization of Ethylbenzene within H-BEA Zeolite","authors":"Peng Liu, Donghai Mei","doi":"10.1021/acs.jpcc.4c07471","DOIUrl":"https://doi.org/10.1021/acs.jpcc.4c07471","url":null,"abstract":"To decipher the reaction network involving ethylbenzene in the petrochemical industry, the monomolecular isomerization process of ethylbenzene to xylene has been studied using density functional theory. With a combination of <i>ab initio</i> molecular dynamics simulations and metadynamics, free energy landscapes characterizing eight elementary steps, viz., ethylidene/methylene transfer, Buchner and retro-Buchner ring expansion, intramolecular hydride transfer, deprotonation of cationic bicyclo[4.1.0] hydrocarbon, and protonation of norcaradiene, have been determined. The Buchner and retro-Buchner ring expansions are found to be the rate-limiting step with the highest free energy barrier of 205 kJ/mol. While the destruction of the cationic diaryl intermediate via the reverse Friedel–Crafts alkylation step is kinetically comparable. Further charge analysis reveals that the highest free energy barrier for the Buchner and retro-Buchner ring expansion step can be attributed to the electron transfer between two strongly positively charged atom groups. This comprehensive computational study offers valuable insights into the intricate details of the ethylbenzene isomerization process, shedding light on the underlying mechanisms of this important reaction in the petrochemical industry.","PeriodicalId":61,"journal":{"name":"The Journal of Physical Chemistry C","volume":"12 1","pages":""},"PeriodicalIF":4.126,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142975629","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electrochemical Oxidative Desorption of Adsorbed Sulfur Species on (111) Surfaces of Single Crystals of Pure Pt and Pt-Based Bimetallic Alloys","authors":"Makoto Aoki, Tamao Shishido, Tetsuro Morooka, Takuya Nakanishi, Takuya Masuda","doi":"10.1021/acs.jpcc.4c06652","DOIUrl":"https://doi.org/10.1021/acs.jpcc.4c06652","url":null,"abstract":"The adsorption/desorption behavior of sulfur species at the (111) surfaces of pure Pt and various Pt-based bimetallic alloys, denoted as Pt₃M (M = Co, Cu, Fe, Pd), was investigated by electrochemical measurements and X-ray photoelectron spectroscopy (XPS). After the adsorption of elemental sulfur, the current responses characteristic of the adsorption/desorption of hydrogen and hydroxyl species at the sulfur-free bare (111) surfaces completely disappeared, and a doublet peak corresponding to the elemental sulfur appeared in the S 2p region of XPS spectra. The characteristic current responses gradually recovered, simultaneously with the decrease of the S 2p peak, by repeating the potential cycling between −0.2 and 0.8 V vs Ag/AgCl, indicating the oxidative desorption of S species. Except for the Pt₃Pd(111) surface, in which Pd has a similar atomic radius to Pt and fully occupied 4d orbitals, the Pt₃M(111) surfaces showed higher oxidative desorption capability than those of the pure Pt(111) surface; electrochemically active surface area recovered at the Pt₃M(111) surfaces by fewer potential cycles than at the Pt(111) surface. Among the various factors, the downshift of the d-band center due to the ligand effect of foreign metal and the electronic interaction between adsorbed S and Pt are the dominant factors promoting the oxidative desorption of sulfur as well as the strain effect of foreign metal with an atomic radius smaller than Pt.","PeriodicalId":61,"journal":{"name":"The Journal of Physical Chemistry C","volume":"22 1","pages":""},"PeriodicalIF":4.126,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142975676","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Theoretical Insight into the Transition-Metal-Embedded Boron Nitride-Doped Graphene Single-Atom Catalysts for Electrochemical Nitrogen Reduction Reaction","authors":"Yuan-Hui Xiao, Zi-Wei Ma, Xin-Wei Wu, Lai-Ke Chen, Zubia Sajid, Rajkumar Devasenathipathy, Jian-De Lin, De-Yin Wu, Zhong-Qun Tian","doi":"10.1021/acs.jpcc.4c04481","DOIUrl":"https://doi.org/10.1021/acs.jpcc.4c04481","url":null,"abstract":"Single-atom catalysts (SACs) have become attractive options for the efficient nitrogen reduction reaction (NRR) because of their unique properties in the activation of nitrogen molecules. As a novel two-dimensional material, boron nitride (BN)-doped graphene has attracted much attention due to its electronic structure, which can be regulated with boron nitride coverage. In the current work, we first screened potential SACs for NRR from various single transition metal atoms embedded in BN-doped graphene (BNC) by using density functional theory (DFT) calculations. Excellent catalytic activity for NRR is demonstrated by the V, Mo, Ru, and Os anchored on the B vacancy and generated SACs, with overpotentials of −0.56, −0.52, −0.60, and −0.61 V vs the standard hydrogen electrode (SHE). Taking advantage of BN-doped graphene electronic structures that can be modified, we further investigated the effect of boron nitride coverage on the SACs’ NRR performance. The electronic structure of the metal center can be altered by controlling the boron nitride coverage, which can further affect the catalytic performance. The potential determining step (PDS) and also the maximal free energy difference vary by modulating the boron nitride coverage. A larger energy range than the hydrogen evolution reaction (HER) is covered by the maximum energy shift between the PDSs, which can reach 0.29 eV. This indicates that by changing the coverage of the BN of the substrate, it is expected to improve the SACs’s catalytic activity and selectivity of NRR. Moreover, it is possible for a pathway to change from one that is adsorption favorable to another one that is thermodynamically favorable of the intermediate NNH. Our results help to clarify the structure–performance correlations and expedite the creation of SACs for ammonia synthesis.","PeriodicalId":61,"journal":{"name":"The Journal of Physical Chemistry C","volume":"127 1","pages":""},"PeriodicalIF":4.126,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142981713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Theoretical Investigation of Polarization-Sensitive Photoresponse in the Donor–Acceptor Interface of Organic Photovoltaic Devices","authors":"Fuzhen Bi, Chiyung Yam, Wu Yang, Junhao Chu, Xichang Bao","doi":"10.1021/acs.jpcc.4c06061","DOIUrl":"https://doi.org/10.1021/acs.jpcc.4c06061","url":null,"abstract":"Understanding the photoelectric conversion process is of great significance for the design and preparation of organic photovoltaic devices. In this work, we investigated the intermolecular and intramolecular photoelectric conversion processes and charge transfer characteristics of donor (D) and acceptor (A) materials at the molecular level by using simulation methods. The nonequilibrium Green’s function method is used to calculate the photocurrents excited by incident photons with different polarization directions. The results show that the photocurrents are optical anisotropy, and the maximum responsivity appears along the specific direction that depends on the incident photon energy. The polarization-sensitive photocurrents are attributed to the anisotropic distribution of photogenerated electrons and holes. Moreover, the integrated photocurrents decrease exponentially with the increase in the π–π stacking distance. However, for the photoexcitation by photons with specific energy, such as 1.18 eV, the photocurrents would increase at first and then decrease as the stacking distance increases; this is due to the energy level splitting caused by the π–π stacking of donor and acceptor molecules. This study proposes a new perspective for understanding photoresponse of the D/A interface, which provides theoretical insights for the advancement of polarized light detection and organic optoelectronics.","PeriodicalId":61,"journal":{"name":"The Journal of Physical Chemistry C","volume":"91 1","pages":""},"PeriodicalIF":4.126,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142975574","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Solvatochromic Dyes Increase the Sensitivity of Nanosensors","authors":"Chen Ma, Tanuja Kistwal, Bjoern F. Hill, Krisztian Neutsch, Sebastian Kruss","doi":"10.1021/acs.jpcc.4c07273","DOIUrl":"https://doi.org/10.1021/acs.jpcc.4c07273","url":null,"abstract":"Organic dyes can be chemically tailored to bind specific molecules and act as molecular sensors or probes. However, they bleach, and most of them fluoresce in the UV–vis range. In contrast, nanomaterials such as single-wall carbon nanotubes (SWCNTs) fluoresce in the near-infrared (NIR) tissue transparency window and are extremely stable. Here, we combine solvatochromic dyes with SWCNTs to create molecular sensors and increase their sensitivity. We find that the dyes <i>trans</i>-4-[4-(dimethylamino)styryl]-1-methylpyridinium iodide (<i>t</i>-DSMI) and Reichardt’s dye (Betaine 30) increase the fluorescence responses of DNA-modified SWCNTs to target analytes. With <i>t</i>-DSMI the fluorescence of (GC)₁₅-SWCNT decreases 4 times more in response to pH changes compared to SWCNTs alone. Betaine 30 also boosts the sensitivity of T₂₀-SWCNT for the lipid linoleic acid (LA) more than 2-fold. A kinetic model shows that not the affinity for the analyte but mainly the fluorescence change is increased by the presence of the solvatochromic dyes. This approach provides a flexible design framework to increase the sensitivity of SWCNTs-based biosensors and combines the best of two worlds.","PeriodicalId":61,"journal":{"name":"The Journal of Physical Chemistry C","volume":"36 1","pages":""},"PeriodicalIF":4.126,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142975583","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Out-of-Plane Piezoelectricity of V2CXY (X/Y = O, S, Se) MXenes Monolayers for Wearable Devices","authors":"Jiao Zhao, Hao-Hao Yang, Kun Xu, Yan-Ru Kang, Han-Wei Li, Shi-Yun Zheng, Fan Xin, Sheng-Xian Wei, Qi Chen, Fang-Biao Wang, Yi-Ming Cao","doi":"10.1021/acs.jpcc.4c06201","DOIUrl":"https://doi.org/10.1021/acs.jpcc.4c06201","url":null,"abstract":"Due to the characteristics of two-dimensional materials, they have demonstrated unique advantages in fields such as piezoelectric devices. Unfortunately, most piezoelectric materials currently do not simultaneously possess excellent piezoelectric effects and mechanical properties. Since the emergence of MXenes, their excellent electrical conductivity and good dynamic and mechanical stability have garnered widespread attention in the energy storage field. Consequently, MXenes are also considered candidates for piezoelectric materials. In this study, the piezoelectric properties and mechanical stability of V₂C<i>XY</i> (V₂COS, V₂CSO, V₂COSe, V₂CSeO) MXenes monolayers were predicted using first-principles methods based on density functional theory. The results indicate that these four materials exhibit good dynamic, thermodynamic, and mechanical stability. It is noteworthy that due to the structural inversion asymmetry and differences in electronegativity, the structure exhibits strong in-plane piezoelectric effects and excellent out-of-plane piezoelectric effects. In particular, the <i>d</i>₃₃ piezoelectric strain coefficient is 2 to 3 orders of magnitude higher than <i>d</i>₂₂ and <i>d</i>₃₁, with the <i>d</i>₃₃ coefficient of V₂CSO reaching up to 313.01 pm/V. This makes these materials highly promising for potential applications in wearable and piezoelectric devices.","PeriodicalId":61,"journal":{"name":"The Journal of Physical Chemistry C","volume":"17 1","pages":""},"PeriodicalIF":4.126,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142975575","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}