Article
Polymer Science
Mujib Ur Rahman, Yonghao Xi, Haipeng Li, Fei Chen, Dongjie Liu, Jinjia Wei
Summary: This study investigated the stability/instability behavior of polystyrene (PS) films of different thickness on silicon substrates, revealing factors such as effective viscosity, solvent strength, and various interactions on the substrate surface that affect the decrement in residual film thickness, growth of holes in the film, and film dewetting. The results showed that the polarity of the rinsing solvent, film thickness, and substrate type impacted the behavior of the polymer film, highlighting the importance of polymer-substrate interactions in determining the overall stability of the PS thin films.
Article
Polymer Science
Sherif Madkour, Marcel Gawek, Andreas Hertwig, Andreas Schoenhals
Summary: The thermodynamic behavior of thin PVME films with an irreversible adsorbed layer on the substrate was studied. Various techniques, including leaching, AFM, ellipsometry, and dielectric spectroscopy, were used to investigate growth kinetics, critical film thickness, influence on glass transition temperature, and molecular dynamics of the adsorbed layer. The study revealed strong percolation effects of the adsorbed layer on thin films.
Article
Chemistry, Physical
Sergio Tosoni
Summary: Mn3O4 Hausmannite thin films supported on (Cu, Ag, Au) coinage metals were investigated using DFT calculations. The interface between the films and metal support exhibited different lattice and ionic match, leading to different interactions. The films on Cu (111) and Au (111) weakly adhered due to unfavorable structural match, while strong adhesion was observed on Ag(100) with commensurate lattice and epitaxial growth. A negative charge flow from the support to the film was reported, resulting in the reduction of the film and an increase in magnetic moments of metal ions in the octahedral sublattice. The ferrimagnetic ordering varied in supported films exposing different crystal faces.
APPLIED SURFACE SCIENCE
(2023)
Article
Chemistry, Analytical
Bianca M. de Lima, Patrick L. Hayes, Paula M. Wood-Adams
Summary: In this study, SFG spectroscopy was used to analyze the lamellar orientation at the surface of semi-crystalline polystyrene thin films, revealing a perpendicular orientation of the chains to the substrate. The study also explored the challenges associated with SFG measurements of heterogeneous surfaces and proposed the correlation between SFG intensity ratios and the progress of crystallization and surface crystallinity. This research demonstrates the potential application of SFG spectroscopy in the conformational analysis of polymeric crystalline structures at interfaces and opens up possibilities for investigating more complex polymeric structures and crystalline arrangements.
ANALYTICA CHIMICA ACTA
(2023)
Article
Polymer Science
Hui Zhang, Tongxin Chang, Shuangshuang Zhang, Kun Zhou, Wei Zhang, Zhijun Hu
Summary: This study provides experimental results on the glass transition temperature changes of nanoconfined polymers and suggests that the decreased chain density at interfaces plays a significant role.
Article
Chemistry, Physical
Canyu Cai, Md Shafiul Azam, Dennis K. Hore
Summary: Understanding the thickness of films and the ability to control angle of incidence allows for selective probing of film interfaces in vibrational sum-frequency generation experiments. A simple theory is presented for planning experiments based on film thickness and refractive index. Discussion on the most complex case where all beams are p-polarized is provided, as this configuration is often necessary for dielectric or metal samples.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Chemistry, Physical
Aigerim Galyamova, Hyunwoo Ha, Graeme Henkelman, Richard M. Crooks
Summary: In this article, a robust experimental model investigating strong metal-support interactions (SMSI) and their impact on electrocatalytic reactions is reported. The beneficial interactions between Ni0.9O thin film supports and PtNPs in the CO electrooxidation reaction are described. The results show negative shifts of the CO electrooxidation peak potential when Ni0.9O thin films are in contact with Pt55 NPs and Pt140 NPs, and the oxygen evolution reaction (OER) is suppressed only when PtNPs are in contact with Ni0.9O thin films. Density functional theory (DFT) calculations attribute the CO electrooxidation enhancement and OER suppression to changes in binding energies at the NiO(111)/Pt55 NP interface.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Masayuki Wakioka, Natsumi Yamashita, Hiroki Mori, Richard Murdey, Takafumi Shimoaka, Nobutaka Shioya, Atsushi Wakamiya, Yasushi Nishihara, Takeshi Hasegawa, Fumiyuki Ozawa
Summary: The cis-to-trans isomerization of poly(thienylenevinylene) has been found to be a feasible method for the fabrication of semiconducting trans-P1 thin films. By thermally annealing the cis-P1 isomer, films with comparable hole mobility to those prepared from the trans-isomer can be obtained. The use of the more soluble cis-isomer allows for the replacement of toxic halogenated solvents with environmentally friendly 2-MeTHF, making solid-state cis-to-trans isomerization an attractive option for sustainable and printable electronics development.
CHEMISTRY OF MATERIALS
(2021)
Article
Chemistry, Physical
Weizhao Ren, Xin Wang, Jiahui Shi, Jianquan Xu, Hidenobu Taneda, Norifumi L. Yamada, Daisuke Kawaguchi, Keiji Tanaka, Xinping Wang
Summary: The adsorbed layer on a solid surface has a complex influence on the dynamics of nanoconfinement polymer materials. This study reveals that the thickness and molecular weight of the adsorbed layer strongly affects the segmental dynamics of supported thin polymer films.
Article
Multidisciplinary Sciences
Zhuocheng Yan, Dong Xu, Zhaoyang Lin, Peiqi Wang, Bocheng Cao, Huaying Ren, Frank Song, Chengzhang Wan, Laiyuan Wang, Jingxuan Zhou, Xun Zhao, Jun Chen, Yu Huang, Xiangfeng Duan
Summary: The conformal integration of electronic systems with irregular, soft objects is crucial for emerging technologies. This study presents the design of van der Waals thin films made of staggered two-dimensional nanosheets, which have bond-free interfaces. These films have sliding and rotation degrees of freedom among the nanosheets, ensuring mechanical stretchability and malleability, as well as a network of nanochannels for permeability and breathability. The films can adapt to the surface topography and seamlessly merge with living organisms, enabling electronic functions such as leaf-gate and skin-gate transistors.
Review
Chemistry, Physical
Mengqi Liu, Senjiang Yu, Linghui He, Yong Ni
Summary: This paper reviews recent progress on the formation and propagation of quasi-static crack patterns in thin films, and summarizes the key factors for choosing different patterns. It also discusses the effect of crack propagation coupled to other stress-relaxation processes on the formation and transition of crack patterns.
Review
Chemistry, Multidisciplinary
Din Zelikovich, Linoy Dery, Hila Sagi-Cohen, Daniel Mandler
Summary: Nanomaterials, especially nanoparticles, have been widely applied in various aspects of our lives, raising concerns about their toxicity and impact on the environment and human health. The activity of nanoparticles depends not only on their composition but also on their size, shape, and surface properties. There is a need for simple methods to distinguish nanoparticles based on their properties, such as imprinting them in soft matrices. This review discusses the current status of nanoparticle imprinting, which combines the principles of molecularly imprinted polymers with the imprinting of larger entities like viruses and bacteria.
Article
Chemistry, Inorganic & Nuclear
Xiaoli Yang, Hongmin Duan, Ruifeng Wang, Fengwang Zhao, Fayi Jin, Wei Jiang, Guangting Han, Qingxin Guan, Haoxi Ben
Summary: The controlled design of Cu-based catalysts and the regulation of their mechanism in CO2 conversion into valuable chemicals remain challenging. In this study, efficient Cu/L catalysts were prepared, and the intrinsic influencing factors on the reaction routes were systematically revealed. It was found that the dispersion of Cu particles and the percentage of Cu-O(OH)-K interfaces played a role in determining the reaction pathways and resulting selectivity.
INORGANIC CHEMISTRY
(2023)
Article
Materials Science, Ceramics
Mingyou Shi, Jinyan Chen, Chao Chen
Summary: The thickness of metallic glass thin films influences their fracture strength and failure mechanisms, with un-notched films transitioning from shear banding to homogeneous deformation as thickness decreases. In contrast, notched films consistently exhibit shear banding regardless of thickness, with a strengthening effect observed near the shear band thickness.
JOURNAL OF NON-CRYSTALLINE SOLIDS
(2022)
Article
Chemistry, Physical
Yuhan Xiao, Pei Bai, Zhengyang Zhang, Yunlong Guo
Summary: This study investigates the nonlinear viscoelastic-viscoplastic properties of thin polymer films, particularly thin polystyrene (PS) films, under nanoconfinement. The results show that with decreasing film thickness, the viscosity and yield stress increase exponentially and linearly, respectively. The observed rubbery stiffening phenomenon in thin PS films may be attributed to induced molecular orientation by plastic deformation.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Biophysics
Aaron Bauer, Santhalingam Elamurugan, Sara A. Tolba, Fatima, Ejjigu Nega, Ivan T. Lima Jr, Wenjie Xia, Dali Sun
Summary: Stereochemical analysis is crucial in understanding biomolecular functions. An elliptical dichroism (ED) spectrometer was constructed for biomedical applications, which demonstrated the potential to analyze secondary structures, conformations, and chirality of biomolecules. It provides a portable, low-cost alternative to the current sophisticated instruments and offers superior features for noninvasive cancer detection.
BIOSENSORS & BIOELECTRONICS
(2023)
Article
Engineering, Environmental
Zhilei Guo, Guohua Jing, Sara A. Tolba, Chung-shin Yuan, Yu-Hua Li, Xiaowei Zhang, Zhiwei Huang, Huawang Zhao, Xiaomin Wu, Huazhen Shen, Wenjie Xia
Summary: The paper presents the design and synthesis of an Au single atom-doped TiO2 catalyst for enhanced Hg-0 oxidation. The O-Au-O coordination environment and orbital interaction were investigated using density functional theory. The synthesized Au SAC Ti1-xO2 catalyst showed significantly improved oxidation capability and resistance to SO2 and NO inhibition compared to conventional TiO2 catalysts.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Chemistry, Physical
Huazhen Shen, Zhilei Guo, Wenjie Xia, Xiaowei Zhang, Zhiwei Huang, Huawang Zhao, Xiaomin Wu, Chung-shin Yuan, Guohua Jing
Summary: 0.1% Au single atom-doped Ti4+ defect TiO2 (0.1% Au-Ti1-xO2) showed high photooxidation efficiency of Hg0 with the assistance of Au-(O)4 coordination, which significantly promoted the separation of photogenerated electron-hole pairs. Additionally, 0.1% Au-Ti1-xO2 exhibited remarkable resistance to SO2 and NO by preventing the deposition of nitrates and sulfates.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Wathsala M. A. Jayawardana, Yangchao Liao, Zhaofan Li, Wenjie Xia, Andrew B. B. Croll
Summary: When a thin sheet is crumpled into a smaller volume, it forms a complex state known as crumpled matter, which exhibits high resistance to compression despite its light weight. This study explores how cutting the sheet affects its behavior in the crumpled state. The findings show that cutting does not significantly change the overall compressive behavior, but it does alter the distribution of curvature in the crumpled sheets.
Article
Chemistry, Multidisciplinary
Zhiqiang Cao, Sara A. Tolba, Zhaofan Li, Gage T. Mason, Yang Wang, Changwoo Do, Simon Rondeau-Gagne, Wenjie Xia, Xiaodan Gu
Summary: Tuning the optoelectronic properties of donor-acceptor conjugated polymers is important in designing organic optoelectronic devices. This study investigates the role of acceptor units and oligothiophene donor units on the energy band gaps of these polymers. The alignment of molecular orbital energy between donor and acceptor units plays a crucial role in determining the final optical bandgap of the polymers. The findings provide molecular insights into the design of D-A CPs for organic optoelectronic devices.
ADVANCED MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Yang Wang, Wenjian Nie, Liang Wang, Dawei Zhang, Kangmin Niu, Wenjie Xia
Summary: In this study, a 4-1 mapping coarse-grained graphene (CGGr) model and the corresponding CG potential TersoffCG(4-1) were developed to accurately reproduce the structure and mechanical properties of graphene. By studying the poly(methyl meth-acrylate) (PMMA) and graphene sheet composite, a predictive CG modeling framework was established to investigate the interfacial behavior at a molecular level. The simulations showed that lower separation velocity and thicker flexible layer can enhance the toughness of the composite by facilitating the formation of craze fibrils.
COMPUTATIONAL MATERIALS SCIENCE
(2023)
Article
Materials Science, Multidisciplinary
Lanping Chen, Wenjie Xia, Taizhong Yao
Summary: In this study, a comprehensive set of features based on chemical composition and physical structure was established, and two accurate and easily interpretable new descriptors were created to predict the formability of perovskite structure. The relationship between the main features and constructed descriptors was analyzed using SHAP and the decision boundary. The selected GBDT classification model successfully screened out 591 novel ABO3-type compounds as high-forming probability perovskite candidates, providing a practical method for rapid screening and identification of potential perovskite candidates.
COMPUTATIONAL MATERIALS SCIENCE
(2023)
Article
Construction & Building Technology
Leonard Chia, Ying Huang, Wenjie Xia, Pan Lu, Dawei Zhang
Summary: This study investigated the dispersion, mechanical and piezoresistive properties of CNT reinforced cementitious composites using carboxymethyl cellulose (CMC) treatment. The experimental results indicated that CMC treatment showed effectiveness in improving CNT dispersion, compressive strength, modulus of elasticity, Poisson ratio, and piezoresistive sensitivity of CNT reinforced cementitious composites.
CONSTRUCTION AND BUILDING MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Yangchao Liao, Zhaofan Li, Long Chen, Andrew B. Croll, Wenjie Xia
Summary: Research has shown that Stone-Wales defects have a strong influence on the crumpling behavior of graphene sheets, affecting their size scaling laws and weakening their self-adhesion. Additionally, these defects lead to enhanced mechanical heterogeneity and a glass-like amorphous state in crumpled graphene.
Article
Chemistry, Multidisciplinary
Yunfei Wang, Song Zhang, Guillaume Freychet, Zhaofan Li, Kai-Lin Chen, Chih-Ting Liu, Zhiqiang Cao, Yu-Cheng Chiu, Wenjie Xia, Xiaodan Gu
Summary: Wearable devices can benefit from the use of stretchable conjugated polymers (CPs). Traditional design assumes that low elastic modulus (E) is crucial for achieving high stretchability, but this research challenges this notion. It is discovered that the degree of entanglement, rather than softness alone, determines stretchability. Even rigid CPs can exhibit high stretchability. Two model CPs with different elastic moduli are studied to further investigate mechanical behavior and deformation mechanisms. By challenging the conventional design metric of low E for high stretchability and highlighting the importance of entanglement, this research hopes to expand the range of CPs available for use in wearable devices.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Polymer Science
Xiangrui Zheng, Wenjian Nie, Yafang Guo, Jack F. Douglas, Wenjie Xia
Summary: We studied the influence of molecular rigidity on the properties of polymer network-forming materials and found that increasing molecular rigidity leads to increased chain size, slower segmental dynamics, and higher temperatures for glass formation. The structural relaxation time and mechanical properties decrease with increasing chain stiffness. Our findings provide insights into the design of cross-linked thermoset materials.
Article
Chemistry, Multidisciplinary
Sarah Ghazanfari, Amirhadi Alesadi, Yangchao Liao, Yida Zhang, Wenjie Xia
Summary: This study investigates the tensile behavior and dynamic heterogeneity of Na-MMT clay under high temperature and pressure conditions using all-atomistic molecular dynamics simulation. The results show that increasing temperature significantly reduces the tensile modulus, strength, and failure strain, while pressure has a minor effect compared to temperature. Mean-square displacement analysis reveals increased molecular stiffness with increasing pressure and decreasing temperature, indicating suppressed atomic mobility. These findings enhance our understanding of the tensile response and dynamical heterogeneity of Na-MMT clay under extreme conditions.
NANOSCALE ADVANCES
(2023)
Article
Chemistry, Multidisciplinary
Arman Ghasemi, Yangchao Liao, Zhaofan Li, Wenjie Xia, Wei Gao
Summary: This study investigates the crystallization and melting behavior of polar and nonpolar polymer chains on monolayers of graphene and graphene oxide using all-atomistic molecular dynamics simulations. The results show that the crystallization behavior of polyvinyl alcohol (PVA) and polyethylene (PE) chains are significantly different, and the presence of oxidation groups on the graphene oxide substrate affects the crystallinity of both PVA and PE chains. Additionally, the melting behavior of 2D crystallized polymer chains depends on their polarity and molecular weight.
Article
Chemistry, Physical
Sara A. Tolba, Wenjie Xia
Summary: Preventing ice formation and accumulation on solid surfaces is a big challenge for engineering applications. Zwitterionic polymer coatings have recently gained attention for their excellent anti-icing performance. This study uses density functional theory to investigate the hydration behaviors of two zwitterionic polymers, revealing the molecular mechanism behind their anti-icing properties. The findings provide valuable insights into water-polymer interactions and have implications for the design of next-generation anti-icing materials.
MOLECULAR SYSTEMS DESIGN & ENGINEERING
(2023)
Article
Chemistry, Multidisciplinary
Yang Wang, Zhaofan Li, Dali Sun, Naisheng Jiang, Kangmin Niu, Andrea Giuntoli, Wenjie Xia
Summary: This study presents a predictive multiscale modeling framework for investigating the temperature-dependent thermomechanical properties of graphene-reinforced poly(3-alkylthiophene) nanocomposites. The results show that the dispersion of graphene decreases with increasing graphene loading. Nanocomposites with shorter P3AT side chains, lower temperatures, and higher graphene content exhibit stronger mechanical responses. The elastic modulus increases linearly with the graphene content, deviating slightly from the Halpin-Tsai micromechanical model prediction. Graphene possesses the highest stiffness, followed by the P3AT backbone and side chains.
