The uniform incorporation of metal and carbon with nanoporous silicon is highly desirable for improving overall Li-storage performance, yet remains a great challenge owing to the different physicochemical properties of Si, M, and C tri-components. Here, we develop an interpenetrating gel-enabled route for uniformly integrating metal and carbon with nanoporous silicon. Specifically, Co and C dual matrices are simultaneously and homogeneously incorporated with nanoporous silicon by magnesiothermically co-reducing an interpenetrating gel, containing SiO2 gel and cyano-bridged In(III)–Co(III) coordination polymer gel networks. Thanks to the nanoporous structure and uniform M/C hybridization, the Si–Co–C ternary material manifests good cycling life (1837 mA h g−1 after 100 cycles at 0.5 A g−1) and superior rate performance (1318 mA h g−1 at 10 A g−1).

Two new quaternary thiosilicate crystalline compounds namely K3Ga3Si7S20 (1) and K2ZnSi3S8 (2) with distinct dimensions were successfully synthesized by the alkali halide flux synthesis method. Both structures feature an anionic M–S–Si (M = Ga or Zn) network constructed from interconnected MS4 and SiS4 tetrahedral units with charge balancing K+ cations. The anionic architecture of 1 is a three-dimensional (3-D) anionic open framework of [(Ga/Si)10S20]n3n− with large channels in which K+ ions are located, while that of 2 presents a two-dimensional (2-D) anionic layer of [ZnSi3S8]n2n− and K+ cations reside in the interlayered spaces. Their physicochemical performances including optical bandgap and thermal behavior were investigated, and the photoelectric response and impedance of 1 were explored. The optical absorption edges of the two compounds are determined to be 3.60 eV (1) and 2.57 eV (2), respectively. In particular, 1 shows good photoelectric response performance, which endows it with broad application prospects in the photoelectric field.

Understanding the relationship between molecular composition/structure and crystal packing is a fundamental challenge in crystal engineering. Planar molecules and planar layer-stacking, as a special group of molecules and a special molecular stacking mode, respectively, occupy special positions in molecular materials. Herein, we constructed two data sets of 1612 planar CHON-containing molecules and a further 65 planar layer-stacked molecules under neither heated nor pressurized conditions, and obtained the composition and structure characteristics thereof. CO and CH molecules do not easily form planar and planar layered structures, respectively. The lowest requirement of the molecular symmetry of plane, Cs, constitutes the largest proportion for both the total planar molecules and the specially planar layer-stacked molecules. In general, high planarity tends to result in planar layer-stacking. Therein, intermolecular hydrogen bonding and the CO group appear frequently to maintain the layers. Still, they are not necessary for the stacking. Additionally, the molecules show packing coefficients (PCs) concentrated within 0.70–0.75, implying a decreasing interlayer distance accompanied by an increasing intralayer intermolecular sparsity. These characteristics of planar and planar layer-stacked CHON-containing molecules are expected to be useful for feature engineering in designing novel molecules.

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S–(CF3)Thianthrenium and S–(CF3)dibenzothiophenium cations form potent chalcogen bonds (ChBs) with [Mo(CO)5CN]−, yielding S2N2 supramolecular motifs. Crystal structures reveal shorter S⋯N contacts opposite the CF3 group compared to the aryl substituents. The energetic features of the ChBs have been studied using DFT calculations demonstrating the structure guiding role of ChBs.

Inspired by morphological control and element doping, nanorod NFS-X ((NiFe)9S8 with different Ni : Fe molar ratios) was synthesized by a hydrothermal method. In this work, uniform and dense NF-X (X = 0, 1, 3, 5, 7, 9 and 10) materials were prepared on NiFe foam, and as a precursor, the nanorod was formed in situ by sulfurization in ethanol. NFS-X (X = 0, 1, 3, 5, 7, 9 and 10) with nanorod morphology was successfully obtained by controlling the Ni and Fe ratio. The optimized NFS-3 has a unique nanorod structure, which provides abundant electrochemical active sites and sufficient electron and electrolyte migration paths for fast and deep Faraday reactions. A specific capacitance of 3620 mF cm−2 at 2 mA cm−2 was obtained with significant cycling performance (83.3% retention after 7000 cycles at 20 mA cm−2). Furthermore, asymmetric supercapacitor CNHC//NFS-3 was prepared by using NFS-3 nanorods as a cathode and double-shell layer Co/Ni-based alkaline carbonate (CNHC) as an anode. The device presents an excellent energy density of 68.9 Wh kg−1 at a power density of 0.74 kW kg−1 while driving a small fan for operation, exhibiting potential for practical applications.

High-quality GaN films on nanoscale patterned sapphire substrates (NPSSs) are required for micro-light-emitting diode (micro-LED) display. In this study, two types of nucleation layers (NLs), including in situ low-temperature grown GaN (LT-GaN) and ex situ physical vapour deposition AlN (PVD-AlN), are applied on cone-shaped NPSS. The coalescence process of GaN grains on the NPSS is modulated by adjusting the three-dimensional (3D) growth temperatures. Results show that low 3D temperatures help to suppress the Ostwald ripening of GaN grains on the NPSS, facilitating the uniform distribution of 3D GaN grains. Higher 3D temperatures lead to a decrease in the edge dislocation density, accompanied by an increase in residual compressive stress. Compared with LT-GaN NLs, PVD-AlN NLs can effectively improve the growth uniformity, suppress the tilting and twisting of GaN grains grown on NPSSs, and promote the orientation consistency of crystal facets during coalescence. The GaN films grown on NPSSs with PVD-AlN NLs exhibit a decrease in the coalescence time from 2000 s to 500 s, a reduction in dislocation densities from 2.8 × 108 cm−2 to 1.4 × 108 cm−2, and an increase in the residual compressive stress from 0.98 GPa to 1.41 GPa compared to those grown on LT-GaN NLs. This study elucidates trends in dislocation and stress evolution in GaN films on NPSSs with analysis of grain coalescence.

The slow kinetic process of the oxygen evolution reaction (OER) and poor electrochemical stability in acidic environments of electrocatalysts seriously restrict the efficiency of hydrogen production from proton exchange membrane water electrolyzers (PEMWEs). In recent years, developing corrosion-resistant and redox-active doped TiO2 with heterogeneous atoms has become an effective strategy to address this challenge. However, most of the reported studies only explore single-element doped TiO2-supported catalysts, and there are few reports comparing the doping effects of various elements at the experimental level, which is crucial for screening high-performance OER electrocatalysts. In this work, seven different metal elements M (M = V, Mn, Fe, Ni, Cu, Nb, W) are selected for doping anatase TiO2 with the same molar ratio (M/Ti) and combined with IrO2 nanoparticles to form M-doped TiO2-supported IrO2 (M–TiO2@IrO2) electrocatalysts. Electrochemical OER activity and stability results indicate that W–TiO2@IrO2 exhibits the best performance among all these catalysts in terms of comprehensively regulating the conductivity of TiO2 and the activity and stability of IrOx within the range of experimental design in this work, which originates from the appropriate energy band structure obtained through W doping, optimizing the intrinsic conductivity of the support and interfacial electronic structure between the metal oxide and support.

To investigate the effect of conformationally flexible molecules on the crystal packing of coordination compounds, eleven mercury(II) complexes containing N-(3-halophenyl)-2-pyridinecarboxamide ligands, carrying different halogen atoms in the ortho-position of the phenyl ring, have been synthesized, molecularly characterized and structurally compared. In this contribution, three various sets of isostructural compounds were obtained by manipulating the proportions of the different solvents and the crystallization temperatures. By varying the reaction conditions three different compositions were observed, and from each composition, independent isostructural series could be observed by halogen replacements. Due to the simultaneous presence of competitive halogen atoms and the flexibility of ligands, conformational preference and altering the kind of halo-atom of ligands can change the nature and type of intermolecular interactions. Despite the presence of isostructurality in the studied compounds, structural diversity is also observed. The structural similarities of these isostructural compounds were interpreted via Hirshfeld surface fingerprint plots, Xpac, and unit cell similarity comparison. Synthon crossover of halogen interaction in coordination compounds of HgX2 was observed, and systematic investigation of halogen⋯halogen interactions utilizing energy calculation was performed. Halogen⋯halogen synthon crossover in coordination compounds has been investigated.

Poly(ε-caprolactone-co-trimethylene carbonate) (PCLTMC) is a biodegradable copolymer, which is widely used for medicine and tissue repair systems, and its morphology, degradation and mechanical properties have been extensively investigated. However, its crystallization behavior with different copolymerization ratios has not been studied systematically, which is of great significance for the study of property regulation and an understanding of the crystallization behavior of random copolymers. In this paper, the relationship between the crystallization temperature Tc, melting point temperature Tm and crystallinity Xc of copolymers with different molar ratios was determined by differential scanning calorimetry (DSC) using a non-isothermal crystallization method. The results show that the melting point and crystallinity of the copolymer decrease with an increase in TMC composition. The equilibrium melting point of the copolymers was predicted by an isothermal crystallization method, using the Hoffman–Weeks extrapolation method and crystallization rate growth fitting method both based on Lauritzen–Hoffman theory. It is proved that Lauritzen–Hoffman theory is of great significance for guiding the kinetic behavior of PCLTMC crystallization.

Despite the considerable potential and significant promise of aluminum scandium nitride (AlScN) ferroelectric materials for neuromorphic computing applications, challenges related to device engineering, along with the considerable structural disorder in thin films grown on various substrates using different vapor synthesis methods, make it difficult to systematically study the structure–property relationship. In this work, we approach such issues from the crystal growth side by successfully growing high-quality single crystal AlScN nanowires through ultra-high vacuum reactive sputtering under high substrate bias and low atomic flux conditions, which leads to simultaneous growth and etching. Characterization of nanowire arrays using X-ray diffraction and transmission electron microscopy shows that the wires are epitaxial single crystals with significantly reduced mosaic spread and predominantly single ferroelectric domains. Moreover, ferroelectric and piezoelectric properties were evaluated using Piezoresponse Force Microscopy. The single crystal AlScN nanowires show an out-of-plane piezoelectric constant d33 that is greater than 20 pm V−1, which is higher than that of pure AlN by a factor of ∼4.

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Networks, consisting of vertices connected by edges, are an important mathematical concept used to describe relationships between people, roads between cities, reactions between chemicals, and many other interactions. Such a network can be created by extracting cocrystals from the Cambridge Structural Database (CSD). This network describes which compounds can form cocrystals together and can, for example, be used to predict new cocrystals using link-prediction techniques. Bipartiteness is an important property of some networks wherein the vertices can be separated into two groups such that edges only point from one group to the other. Knowing whether a network is bipartite can make studying its structure considerably easier. If a network is nearly bipartite except for a number of outlying edges, one might want to identify and remove those edges, thereby bipartising the network. The CSD cocrystal network was previously found to be close to bipartiteness. Truly bipartising it could improve the accuracy of link-prediction and give insight into the hidden structure of the network. Many algorithms exist for exactly finding the optimal bipartisation for a nearly-bipartite network, but the time it takes to complete such algorithms increases exponentially with the size of the problem. In some cases, an exact solution is unnecessary and a ‘good enough’ bipartisation is sufficient. We have developed an algorithm that can find a near-optimal bipartisation within reasonable time, even for very large networks, and used it to unravel the structure of the CSD cocrystal network. We obtained a bipartisation that leaves 96% of the network intact, and we were able to identify ‘universal’ coformers that do not conform to the bipartite nature of the network. By applying a clustering algorithm to the bipartised network, we were also able to identify anticommunities of coformers.

A single crystal of Zn2Te3O8 (ZTO) was grown using the conventional Czochralski technique. TGA analysis showed that the melting point of ZTO is 681 °C, while it exhibits a structural phase transition at 621 °C. The powder X-ray diffraction analysis of ZTO confirmed that it possesses a single crystalline monoclinic structure with the C2/c space group. An indirect band gap of 3.75 eV was estimated for the ZTO crystal based on its absorption spectrum. The X-ray-induced luminescence of the grown crystal comprised a broad band peaking at 565 nm, which can be tentatively assigned to the self-trapped exciton emission from the (Te3O8)4− molecular complexes. The photoluminescence measured under 280 nm excitation showed a broad band luminescence peaking at about 600 nm, and its intensity was significantly enhanced upon cooling the crystal from 300 K to 10 K. The photoluminescence decay time under 280 nm excitation was shown to have two exponential components in the range from 10 K to 175 K, which became a single exponential upon further heating the crystal. Low scintillation light was observed at room temperature both under α- and β-particle excitations from 241Am and 90Sr sources, respectively. The scintillation light yield measured under β-particle excitation from the 90Sr source was enhanced by about five orders of magnitude at 10 K in comparison to that at 300 K. The scintillation light yield measured at 10 K under the same experimental conditions for ZTO in comparison with the well-known cryogenic scintillator Li2MoO4 (LMO) was shown to have four times higher scintillation light. A single-crystal ingot of ZTO was obtained for the first time; however, it had several cracks due to its phase transition. Notably, scintillation at low temperatures for a Te-based crystal was observed for the first time. These preliminary findings are very promising and show that ZTO will be a good candidate for cryogenic phonon scintillation detectors for the 0νββ decay search of 130Te.

Laser induced damage sites on the surface of a KDP crystal component tend to grow with subsequent laser irradiation, which substantially decrease the lifetime of these optics. The structural investigation suggests that this may be related to the surface damage products of the crystals. In this work, the differences in the crystal structures, electronic properties and optical absorption between the KDP crystal and its surface laser-induced decomposition products K2H2P2O7 and KPO3 are investigated by using first-principles calculations. The theoretical results show that the nonlinear optical active units of KDP crystals are disrupted after irradiation dehydration to K2H2P2O7 and KPO3, which leads to the optical properties at the surface damage being deteriorated. In terms of the electronic structure, the dehydration products K2H2P2O7 and KPO3 have a shorter band gap compared with the KDP crystal. In addition, K2H2P2O7 and KPO3 have a wider optical absorption band than that of the KDP crystal and introduce more ultraviolet absorption in the optical elements. Compared to polycrystalline KDP at the bulk damage sites, the dehydration products at the surface damage increase the ultraviolet absorption of the crystals and cause the surface damage to continually grow under subsequent irradiation, whereas the bulk damage does not continue to increase in subsequent laser irradiation.

Recently, the co-crystallization of pharmaceutical drugs is gaining consideration because it is an environmentally friendly and potentially effective technique to improve the solubility and bioavailability of poorly soluble drugs without altering the chemical identity or reducing the biological activity or therapeutic effect of the active pharmaceutical ingredient (API). The co-crystallization process in the pharmaceutical industry is still not fully utilized owing to the limited methods for large-scale production. However, it is a very convenient, appropriate, and green technique in the field of drug development research as only a few synthetic steps are involved with the minimal or no use of solvents. Herein, the selection criteria or the factors that affect the selection of coformers in this process are discussed. In addition, the different stages of co-crystal manufacturing, from the screening phase to industrial production, are identified and the use of continuous and scalable methods in co-crystal production as well as the implementation of quality-by-design and process analytical technology concepts are addressed. The potential pharmaceutical applications, like the enhancement in drug solubility, and the drug dissolution rate, which consequently leads to improved bioavailability and therapeutic efficacy, are also highlighted. This study briefly reviews different strategies for enhancing the solubility of poorly soluble drugs with a special emphasis on co-crystal formation, including solvent-based and solvent-free methods of production.

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Urease is an enzyme that catalyzes the hydrolysis of urea to ammonia and carbon dioxide. Accordingly, the addition of urease inhibitors can delay the hydrolysis of urea, and thus improve the fertilizer efficiency. Herein, a new N-donor ligand, 5-hydroxy-N1,N3-di(pyridin-3-yl)isophthalamide, was synthesized and combined with different types of acids to prepare two Cu-based coordination polymers (Cu-CPs), namely, [Cu(3-dpip)(1,3,5-HBTC)] (Cu-CP-COOH) and [Cu2(3-dpip)(5-NIP)2(H2O)2] (Cu-CP-NO2), where 1,3,5-H3BTC = 1,3,5-benzenetricarboxylic acid and 5-H2NIP = 5-nitroisophthalic acid, which served as urease inhibitors (UIs) and showed excellent inhibition with IC50 values of 1.60 ± 0.01 μM for Cu-CP-COOH and 1.24 ± 0.01 μM for Cu-CP-NO2. The role of Cu-CP-COOH and Cu-CP-NO2 in the kinetics of urease inhibition was also investigated and the Lineweaver–Burk (L–B) curves indicated that both inhibitors were anti-competitive inhibitors. A virtual screen for urease showed binding energies of −10.28 kcal mol−1 for Cu-CP-COOH and −11.34 kcal mol−1 for Cu-CP-NO2. More importantly, 5-R-isophthalic acid (R = –COOH and –NO2) played an important role in urease inhibition activity. The structure–function relationship was further discussed, which indicates that Cu-CPs can be used as a type of UI.

The main emphasis of the present Highlight paper is to summarise reported works aiming to understand the effect of sulfur and nitrogen doping on graphene nanoplatelets for high capacity electrodes in solid-state rechargeable energy storage devices. Lithium-ion batteries are considered to be one of the most promising energy storage devices which have the potential of integrating the high energy granted by lithium-ion batteries and long cycling life of supercapacitors in the same system. However, the present Li-ion batteries provide only high power density due to the low electrical conductivity of the anode materials. Moreover, there is a need to increase the capacity and kinetic imbalances between the anode and cathode by designing high-power and stable structures for the anode and cathode materials. Graphene nanoplatelets (GnPs) have been intensively explored as anode materials in lithium ion batteries due to their unique structure and outstanding electrochemical properties. The synthesis procedure, structure and electrochemical performance of such materials are discussed extensively in this manuscript.

Flow systems enable in-line synthesis and processing of organic materials in a continuous reaction pathway, which is advantageous for high-throughput and scale-up. In this work, a highly crystalline TAPB-OHPDA covalent organic framework (COF) was directly crystallized under continuous flow conditions in as little as 30 minutes. Brunauer–Emmett–Teller (BET) surface analysis reveals high surface areas greater than 1700 m2 g−1 can be afforded in 2 hours, resulting in a 36× faster processing time compared to a majority of other reported solvothermal methods. Additionally, the crystalline COF material was also washed with solvent in flow to reduce the required post-processing burden typically performed iteratively during purification and activation. The results presented herein provide foundational knowledge for COF syntheses under packed-bed flow conditions and reveal an opportunity to accelerate the formation and processing of highly crystalline COF materials.