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1. Engineering Colossal Anisotropic Thermal Expansion into Organic Materials through Dimensionality Control

   https://doi.org/10.1021/acs.chemmater.3c01677  

   Juneja, Navkiran; Unruh, Daniel K.; Hutchins, Kristin M. (September 2023, Chemistry of Materials)

   Thermal expansion (TE) behavior in solid-state materials is influenced by both molecular and supramolecular structure. For solid-state materials assembled through covalent bonds, such as carbon allotropes, solids with higher dimensionality (i.e., diamond) exhibit less TE than solids with lower dimensionality (e.g., fullerene, graphite). Thus, as the dimensionality of the solid increases, the TE decreases. However, an analogous and systematic variation of the dimensionality in solid-state materials assembled through noncovalent bonds with a correlation to TE has not been studied. Here, we designed a series of solids based on dimensional hierarchy to afford materials with zero-dimensional (0D), 1D, and 2D hydrogen-bonded structures. The 2D materials are structural analogues of graphite and covalent-organic frameworks, and we demonstrate that these 2D solids exhibit unique biaxial zero TE with anisotropic and colossal TE along the π-stacked direction (α ∼ 200 MK–1). The overall behavior in the 2D hydrogen-bonded solids is similar to 2D covalent-bonded solids; however, the coefficient of TE along the π-stacked direction for these hydrogen-bonded solids is an order of magnitude higher than in 2D graphite or phosphorus allotropes. The hierarchal materials design strategy and correlation to TE properties described herein can be broadly applied to the design and synthesis of new solid-state materials sustained by covalent or noncovalent bonds with control over solid-state behaviors. 

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2. Large scale self-assembly of plasmonic nanoparticles on deformed graphene templates

   https://doi.org/10.1038/s41598-021-91697-z  

   Gole, Matthew T.; Yin, Zhewen; Wang, Michael Cai; Lin, Wayne; Zhou, Ziran; Leem, Juyoung; Takekuma, Satoshi; Murphy, Catherine J.; Nam, SungWoo (December 2021, Scientific Reports)

   Abstract Hierarchical heterostructures of two-dimensional (2D) nanomaterials are versatile platforms for nanoscale optoelectronics. Further coupling of these 2D materials with plasmonic nanostructures, especially in non-close-packed morphologies, imparts new metastructural properties such as increased photosensitivity as well as spectral selectivity and range. However, the integration of plasmonic nanoparticles with 2D materials has largely been limited to lithographic patterning and/or undefined deposition of metallic structures. Here we show that colloidally synthesized zero-dimensional (0D) gold nanoparticles of various sizes can be deterministically self-assembled in highly-ordered, anisotropic, non-close-packed, multi-scale morphologies with templates designed from instability-driven, deformed 2D nanomaterials. The anisotropic plasmonic coupling of the particle arrays exhibits emergent polarization-dependent absorbance in the visible to near-IR regions. Additionally, controllable metasurface arrays of nanoparticles by functionalization with varying polymer brushes modulate the plasmonic coupling between polarization dependent and independent assemblies. This self-assembly method shows potential for bottom-up nanomanufacturing of diverse optoelectronic components and can potentially be adapted to a wide array of nanoscale 0D, 1D, and 2D materials. 

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3. Building Manganese Halide Hybrid Materials with 0D, 1D, and 2D Dimensionalities

   https://doi.org/10.3390/cryst13121634  

   Peoble, Anna; Gallegos, Kandee; Ozide, Michael O.; Castañeda, Raúl (December 2023, Crystals)

   In recent years, metal-halide hybrid materials have attracted considerable attention because materials, such as lead-iodide perovskites, can have excellent properties as photovoltaics, light-emitting devices, and photodetectors. These materials can be obtained in different dimensionalities (1D, 2D, and 3D), which directly affects their properties. In this article, we built 0D, 1D, and 2D manganese halide materials with 3-aminopyridine (3AP) or 4-ethylpyridine (4EtP). Two isomorphic complexes with 3AP and manganese chloride ([MnCl2(3AP)4]) or manganese bromide ([MnBr2(3AP)4]) were obtained with the amino group in 3AP assisting in the formation of 0D structures via hydrogen bonding. By modifying the reaction conditions, 3AP can also be used to build a 2D coordination polymer with manganese chloride ([MnCl33AP]− [3APH]+). Unlike 3AP, 4EtP does not provide the opportunity for hydrogen bonding, leading to the formation of two additional isomorphic compounds built of individual 1D chains with manganese chloride ({MnCl3(4EtP)2}n) and manganese bromide ({MnBr2(4EtP)2}n). In the visible region, the 0D and 1D manganese halide compounds have similar photoluminescence properties; however, 0D and 1D have different near-IR emissions. In conclusion, hydrogen-bonding groups can play a role in the formation of discrete manganese-halide units, 1D halide chains, or 2D polymeric sheets. 

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4. Effect of Tungsten Oxide Nanostructures on Sensitivity and Selectivity of Pollution Gases

   https://doi.org/10.3390/s20174801  

   An, Fenghui; Zhou, Andrew F.; Feng, Peter X. (September 2020, Sensors)

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   We report on the different surface structures of tungsten oxides which have been synthesized using a simple post-annealing-free hot-filament CVD technique, including 0D nanoparticles (NPs), 1D nanorods (NRs), and 2D nanosheet assemblies of 3D hierarchical nanoflowers (NFs). The surface morphologies, crystalline structures, and material compositions have been characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and Raman spectroscopy, respectively. The sensor performances based on the synthesized samples of various surface morphologies have been investigated, as well as the influences of operating temperature and applied bias. The sensing property depends closely on the surface morphology, and the 3D hierarchical nanoflowers-based gas sensor offers the best sensitivity and fastest response time to NH3 and CH3 gases when operated at room temperature. 

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5. 2D MXene-containing polymer electrolytes for all-solid-state lithium metal batteries

   https://doi.org/10.1039/C8NA00206A  

   Pan, Qiwei; Zheng, Yongwei; Kota, Sankalp; Huang, Weichun; Wang, Shijun; Qi, Hao; Kim, Seyong; Tu, Yingfeng; Barsoum, Michel W.; Li, Christopher Y. (January 2019, Nanoscale Advances)

   Nanocomposite polymer electrolytes (CPEs) are promising materials for all-solid-state lithium metal batteries (LMBs) due to their enhanced ionic conductivities and stability to the lithium anode. MXenes are a new two-dimensional, 2D, family of early transition metal carbides and nitrides, which have a high aspect ratio and a hydrophilic surface. Herein, using a green, facile aqueous solution blending method, we uniformly dispersed small amounts of Ti 3 C 2 T x into a poly(ethylene oxide)/LiTFSI complex (PEO 20 -LiTFSI) to fabricate MXene-based CPEs (MCPEs). The addition of the 2D flakes to PEO simultaneously retards PEO crystallization and enhances its segmental motion. Compared to the 0D and 1D nanofillers, MXenes show higher efficiency in ionic conductivity enhancement and improvement in the performance of LMBs. The CPE with 3.6 wt% MXene shows the highest ionic conductivity at room temperature (2.2 × 10 −5 S m −1 at 28 °C). An LMB using MCPE with only 1.5 wt% MXene shows rate capability and stability comparable with that of the state-of-the-art CPELMBs. We attribute the excellent performance to the 2D geometry of the filler, the good dispersion of the flakes in the polymer matrix, and the functional group-rich surface. 

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