Growth Of Organic Crystals Research Articles

Centimeter-Scale Assembly of Fractal Organic Crystals with Crisscross Structures for Flexible Photosynapses.

Fractal assembly technology enables scalable construction of organic crystal patterns for emerging nanoelectronics and optoelectronics. Here, a polymer-templating assembly strategy is presented for centimeter-scale patterned growth of fractal organic crystals (FOCs). These structures are formed by drop-coating perylene solution directly onto a gelatin-modified surface, resulting in the formation of crisscross fractal patterns. By adjusting the tilt angle of the template, the morphology of FOCs can be effectively controlled, with the diameter distribution of each level branch ranging from hundreds to ten micrometers. The planar FOC device exhibits flexible photoreception and photosynaptic capabilities, with a high specific detectivity of 1.35×109 Jones and paired-pulse facilitation (PPF) index of 104%, withstanding a 0.5cm bending radius during bending test. These findings present a reliable route for large-scale assembly of flexible organic crystalline materials toward neuromorphic electronics.

Exploring the impact of solvent on growth, morphology and photoluminescence properties of organic electro-optic OH1 single crystal

Exploring the impact of solvent on growth, morphology and photoluminescence properties of organic electro-optic OH1 single crystal

Growth and characterization of organic 4-chloroaniline single crystals for nonlinear optical applications

Growth and characterization of organic 4-chloroaniline single crystals for nonlinear optical applications

Fast growth of large-sized organic single crystals via spin coating

Spin-coating stands out as one of the fastest and simplest processes for material solidification. While it is commonly employed for producing polycrystalline thin films, recent endeavors have explored its potential for epitaxial growth, albeit primarily limited to inorganic materials. In this study, we demonstrate the spin-coating method enabling the rapid growth of large-sized organic single crystals (OSCs). Within 2 h, we successfully obtained OSCs with controlled lateral sizes of up to 2 mm, which conventionally takes several weeks using slow solvent evaporation. Raman mapping and UV–Vis absorption measurements confirmed the growths of the OSCs. We propose the growth mechanism by using the supersaturated dynamic fluid model. Furthermore, we demonstrate the device integration of these OSCs for charge-transfer complex channel, revealing ambipolar behavior during gate sweep. This innovative OSCs production method has the potential to advance the various field of science and electronics, traditionally hindered by the scarcity of adequately sized OSCs.

Growth and characterization of organic p-nitroacetophenone single crystals for nonlinear optical applications

Growth and characterization of organic p-nitroacetophenone single crystals for nonlinear optical applications

Controlling Fluorination Density of Soluble Polyimide Gate Dielectrics and its Influence on Organic Crystal Growth and Device Operational Stability.

Fluorinated polyimides (PIs) are among the most promising candidates for gate dielectric materials in organic electronic devices because of their solution processability and outstanding chemical, mechanical, and thermal stabilities. Additionally, fluorine (F) substitution improves the electrical properties of PI thin films, such as enhanced dielectric properties and reduced surface trap densities. However, the relationship between the fluorination density of PIs and crystal growth modes of vacuum-deposited conjugated molecules on PI thin films, which is directly related to the lateral charge transport along the PI-organic semiconductor interface, has not been systematically studied. Herein, five different soluble PIs with different F densities were synthesized, and the correlation between fluorination and thin-film properties was systematically investigated. Not only were their dielectric properties modulated, but the growth modes of the organic molecules deposited on the PI thin films also changed with increasing surface F density. This phenomenon was observed by both surface and crystallographic analyses, which resulted in extremely high operational stability of field-effect transistors and the successful fabrication of organic complementary circuits. We believe that the correlation between PI backbone fluorination and its thin-film properties will provide practical insights into the material design based on controlled molecular directed surface assembly on fluorinated polymer dielectrics.

Synthesis and growth of organic 2-ethylimidazolium hydrogen diglycolate single crystal for nonlinear optical applications

A single crystal of 2-Ethylimidazolium hydrogen diglycolate (DAEI) has been grown by slow evaporation solution (SEST) technique at 35 °C. The DAEI crystal belongs to a monoclinic crystal system with a P21/c space group. The Hirshfeld surface analysis determined the grown crystal has the highest intermolecular contribution for O..H interaction. The phase purity and various planes (hkl) of the DAEI crystal system were determined by powder X-ray diffraction analysis (PXRD). The functional groups and their different vibrations of DAEI crystal were identified by Fourier transform infrared analysis. The band gap energy value of the DAEI crystal is found to be 5.32 eV. Photoluminescence measurement reveals that the DAEI crystal has green emission. The material shows major weight losses of around 82.45 % in the temperature between 140 °C and 300 °C. The dielectric analyses were carried out for different frequencies (1Hz–1MHz) and different temperatures. The third-order nonlinear optical properties such as refractive index (n2), absorption coefficient (β) and susceptibility (χ(3)) were determined using the Z-scan technique using a He–Ne laser (λ = 632.8 nm).

MOR nanosheets with tunable c-axis thickness and their catalytic performance in DME carbonylation

Controlling the anisotropic growth of crystals to achieve desired morphology is a challenge in zeolite crystallization, which often requires the use of bulky organic surfactants or additional crystal growth modifiers. Here, MOR crystals with tunable c-axis thickness (12-MR channel direction) were readily synthesized with commercial tetraethylammonium hydroxide (TEAOH) as an organic-structure directing agent (OSDA). It is revealed that the relative growth rates of different crystal faces of MOR zeolite can be tuned by the crystallization temperature and TEAOH amount in the developed gel system. Higher temperature and lower TEAOH concentration can effectively retard the growth of MOR crystals along the c-axis, yielding MOR nanosheets with short c-axis thickness (ca. 40 nm). Investigation on the crystallization process demonstrates that the crystal growth follows a particle attachment mechanism. Theoretical calculation was further employed to elucidate the c-axis thickness variation of MOR zeolite under different conditions. A kilogram-scale synthesis of MOR nanosheets has been realized with a 10 L autoclave, achieving high solid yield of 92 %. The MOR nanosheets, offering short 12-MR diffusion path, exhibit substantially enhanced catalytic activity and stability in the dimethyl ether (DME) carbonylation to methyl acetate reaction.

Crystal growth and morphology control of needle-shaped organic crystals

In this highlight fundamental research on the growth of needle-like crystals and strategies to control the aspect ratio are reviewed.

Growth and characterization of organic 2-methylbenzimidazole 4-Aminobenzoate Single crystal for Opto-electronic device applications

A new organic material of 2-Methylbenzimidazole 4-Aminobenzoate (2MIAB) with a size of 5 × 4 × 3 mm3 was grown by solvent evaporation solution growth method. The SCXRD studies reveal that the 2MIAB crystal has a monoclinic crystal structure and belongs to the space group P21/nn number is 4 unit cell parameters are a=7.8319(3) Å, b=20.6465(8) Å, c=9.0432(3) Å, α =90°, β =90.4140°, γ =90°and V =1462.26(9) Å 3. The hkl planes are identified through Powder XRD analysis. The functional groups present in the 2MIAB crystal were determined from FTIR spectral analysis. The UV–Vis spectral analysis of 2MIAB shows a high transmittance range of 99% and a cut-off wavelength of approximately 315 nm. The surface morphology of the 2MIAB compound is examined through FE-SEM analysis. The thermal studies reveal that the grown crystal is stable up to 134 °C. dielectric constant in free space (ϵ0) and dielectric loss (tanδ) of 2MIAB crystal at varying temperatures (313 K, 323 K, 333 K) are recorded with a frequency range of 50 Hz to 5 MHz. The load-dependent hardness of the 2MIAB crystal was analyzed using Vicker’s microhardness test. The optical limiting was performed by Q-switch Nd: YAG laser with a wavelength of 532 nm and intensity of 2.46×1012 W/m2 (pulse rate of 9 ns and energy of 100 μJ ). We employed First-principles density functional theory and ab-initio molecular dynamics simulations to study the electronic and optical properties of the 2MIAB material. We demonstrate that this material is semiconductor in nature, with an energy band gap of 3.26 eV and significant absorption in the UV light range.

Exploring the mechanism of asymmetric growth of organic polar crystals: Inherent properties, specific intermolecular interactions

Organic polar crystals (OPCs) are the foundation for photonic and non-linear optical applications in advanced materials. High-quality crystals are a key in achieving efficient performance for OPCs. This work explores the properties and mechanisms of OPC growth along the polar axis. Melt microdrop growth experiments confirm that asymmetric growth is an inherent property of OPCs and relates to the intrinsic crystal structure. Notably, the solvent also plays a non-negligible role in OPCs growth. Solvent-crystal face interactions are strongly influenced by the crystal face structure. A rough surface has a slower growth rate, and a specific recognition of the solvent molecules. Asymmetric growth correlates with the modified attachment energy model and reveals the role of the solvent in inhibiting of crystal growth. Finally, the growth pattern in different solvents is explained by the interfacial adsorption model. This work will further enrich the asymmetric growth mechanism of OPCs and provide guidance for obtaining high-quality OPCs in solution.

Self‐Limited Epitaxial Growth of Patterned Monolayer Organic Crystals for Polarization‐Sensitive Phototransistor with Ultrahigh Dichroic Ratio

AbstractMonolayer organic crystals provide an unprecedented opportunity for studies on the intrinsic charge transport of organic semiconductors because of their 2D nature that is free of grain boundaries with fewer defects. However, due to the spatially stochastic molecular nucleation and the difficulty in controlling monolayer assembly, large‐scale growth of monolayer organic crystals remains a formidable challenge. Here, a self‐limited epitaxial growth strategy is proposed to realize large‐area patterned growth of monolayer organic crystals via physical vapor deposition process. Specifically, this approach confines the molecular nucleation and crystallization in defined wetting patterns, whose sizes are smaller than the mean free path of the molecules on substrate, enabling the formation of a single nucleus in wetting pattern. Meanwhile, the intermolecular lattice mismatch between 2,7‐dialkyl[1]benzothieno[3,2‐b][1]benzothiophene (Cn‐BTBT, n = 8 and 10) derivatives inhibits vertical molecular stacking, thereby promoting the monolayer assembly of organic molecules. Using this approach, centimeter‐sized patterned growth of mixed Cn‐BTBT monolayer organic crystals is achieved. Polarization‐sensitive phototransistors based on the monolayer organic crystals exhibit ultrahigh dichroic ratio up to 4.6 × 103, on par with the commercial polarizers (103). This work sheds light on large‐scale patterned growth of monolayer organic crystals toward high‐performance optoelectronic devices.

Growth and characterization of organic 4-hydroxybenzophenone single crystals for nonlinear optical applications

Growth and characterization of organic 4-hydroxybenzophenone single crystals for nonlinear optical applications

Recent Advances in the Asymmetric Growth of Organic Polar Crystals: A Review

Recent Advances in the Asymmetric Growth of Organic Polar Crystals: A Review

Wafer-Scale Epitaxial Growth of Two-dimensional Organic Semiconductor Single Crystals toward High-Performance Transistors.

The success of state-of-the-art electronics and optoelectronics relies heavily on the capability to fabricate semiconductor single-crystal wafers. However, the conventional epitaxial growth strategy for inorganic wafers is invalid for growing organic semiconductor single crystals due to the lack of lattice-matched epitaxial substrates and intricate nucleation behaviors, severely impeding the advancement of organic single-crystal electronics. Here, an anchored crystal-seed epitaxial growth method for wafer-scale growth of 2D organic semiconductor single crystals is developed for the first time. The crystal seed is firmly anchored on the viscous liquid surface, ensuring the steady epitaxial growth of organic single crystals from the crystal seed. The atomically flat liquid surface effectively eliminates the disturbance from substrate defects and greatly enhances the 2D growth of organic crystals. Using this approach, a wafer-scale few-layer bis(triethylsilythynyl)-anthradithphene (Dif-TES-ADT) single crystal is formed, yielding a breakthrough for organic field-effect transistors with a high reliable mobility up to 8.6 cm2 V-1 s-1 and an ultralow mobility variable coefficient of 8.9%. This work opens a new avenue to fabricate organic single-crystal wafers for high-performance organic electronics.

Disordered Phase-Assisted Growth of Organic Semiconductor Crystals on Self-Assembled Monolayer Templates.

Achieving high mobility and bias stability is a challenging obstacle in the advancement of organic thin-film transistors (OTFTs). To this end, the fabrication of high-quality organic semiconductor (OSC) thin films is critical for OTFTs. Self-assembled monolayers (SAMs) have been used as growth templates for high-crystalline OSC thin films. Despite significant research progress in the growth of OSC on SAMs, a detailed understanding of the growth mechanism of the OSC thin films on a SAM template is lacking, which has limited its use. In this study, the effects of the structure (thickness and molecular packing) of SAM on the nucleation and growth behavior of the OSC thin films were investigated. We found that disordered SAM molecules assisted in the surface diffusion of the OSC molecules and resulted in a small nucleation density and large grain size of the OSC thin films. Moreover, a thick SAM with disordered SAM molecules on the top was found to be beneficial for the high mobility and bias stability of the OTFTs.

Growth, structural, optical, and thermal behavior of bibenzyl organic single crystal for scintillator applications

Growth, structural, optical, and thermal behavior of bibenzyl organic single crystal for scintillator applications

Understanding the agglomerate crystallisation of hexamine through X-ray microscopy and crystallographic modelling

The detailed molecular-scale mechanism of the growth of organic crystals underpins a diversity of phenomena, such as the isolation and purification of high-quality materials for the pharmaceutical and fine chemical sectors. Recent advances in X-ray Microscopy (XRM) and complementary diffraction contrast tomography (DCT) have enabled the detailed characterisation of the micro-structure of hexamine agglomerates. Detailed XRM analysis of the growth history and micro-structure of such agglomerates reveals a highly orientated epitaxial inter-relationship between their constituent micro-crystallites. This is found to be consistent with a secondary nucleation growth mechanism associated with re-growth at the 3-fold corner sites within the crystals’ dominant {110} dodecahedral morphology. The agglomeration appears to heal upon further growth as the aligned agglomerated micro-crystals connect and fuse together but, in doing so, pockets of inter-crystallite mother liquor become trapped forming a symmetric pattern of solvent inclusions. The mechanistic origin of this phenomenon is rationalised with respect to historical data together with an analysis of the solid-state chemistry of the compound through the development of a ‘snow flake’ model. The latter draws upon hexamine’s propensity for edge growth instabilities with increasing crystal size as well as its tendency for unstable growth at the facet corners along the 〈111〉 directions, a situation compounded by the lack of growth-promoting dislocations at the centers of the {110} habit surfaces. The agglomerative mechanism presented here could apply to other high symmetry crystal systems, particularly those whose crystal structures involve centred Bravais lattices and where the dominant inter-molecular interactions are angled towards the facet edges.

Organic Crystal Growth: Hierarchical Self-Assembly Involving Nonclassical and Classical Steps

Organic crystal nucleation and growth are complex processes that often do not fit into the framework of the existing crystallization theories. We investigated a crystal growth mechanism of an organic dye, perylene diimide, using high-resolution cryogenic transmission electron microscopy and optical spectroscopy. The elucidated mechanism involves classical (monomer attachments) and nonclassical pathways, exhibiting a self-assembly sequence where all steps are interconnected. It starts from the assembly of molecular π-stacks that are initially disordered. They gradually optimize their structure, rigidify, and interact to form crystalline domains. The latter further evolve via the addition of individual molecules, and crystal fusion (via oriented attachment). All the observed supramolecular transformations are connected and follow a clear hierarchy starting from the molecular-scale interactions. The elucidation of the complex pathway of organic crystallization as a series of coordinated supramolecular transformations at multiple scales conceptually advances the understanding of order evolution in organic matter.

Vapor‐Phase Growth Strategies of Fabricating Organic Crystals for Optoelectronic Applications

AbstractVapor‐phase growth methods, taking the advantages of producing high‐quality crystals with low defects, thin thickness, and homogeneous composition, are of great significance in the field of organic crystal growth and their high‐performance applications. At present, the requirements for organic crystals as building blocks for the construction of optoelectronic devices are increasing with the constant advances in organic optoelectronics. Therefore, the vapor‐phase growth method would become one of the practical techniques that cannot be ignored to fabricate organic crystals. In this paper, an overview of different vapor‐phase growth methods for the preparation of organic single crystals is provided. An introduction to the current status of the vapor phase method is presented and the view on the challenges it faces with some promising solution ideas. It is believed that this review will serve as a reference for further development and an inspiration for the new way forward.