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The type II band alignment of 0D/2D GQDs–MoS2 is realized by increasing the size of GQDs, beneficial to photocatalysis.

Zeolite supported amorphous zirconia layer with high specific surface area, abundant adsorption sites and excellent reusability hold a bright prospect in phosphate adsorption, yet it is proven to be still challenging to precisely regulate its synthesis.

g-C3N4/TiO2 heterojunction functional foams were constructed as gas purification filters for treating NO indoor gas with a high removal rate (>65%) and high stability under visible-light (λ ≥ 400 nm) illumination. The skeletons of the 3D foams consisted of g-C3N4 and TiO2 quantum dots (QDs). Such 3D porous foamy filters provided a large surface area and continuous pores for trapping and oxidizing NO molecules owing to their excellent adsorption and activation capability. The embedded g-C3N4/TiO2 QD heterojunctions in the foam skeletons effectively promoted the separation of photo-generated carriers, allowing the generation of more active species (holes and ˙OH) for oxidizing NO molecules. An oxidation pathway (NO → NO+ → NO2− or NO3−) was proposed based on in situ FTIR spectroscopy, which suggested the important role of NO+ for removing NO gas. This work provides an efficient and stable air-purification filter for indoor air treatment.

In order to maintain the thermal stability of SOT devices with nanoscale size, it is desirable to achieve current induced magnetic switching in magnetic materials with high perpendicular anisotropy. In the present paper, current induced field-free switching of FePt/[TiN/NiFe]5 is achieved by interlayer exchange coupling, in which in-plane magnetized NiFe serves as a coupling layer through a TiN space layer. The large Ku (1.03 × 107 erg cc−1) and low critical current density values (0.17 × 107 A cm−2) show great advantages in thermal stability and energy consumption. Interestingly, it is found that the rotation directions of the current-induced magnetic switching loops under different applied magnetic fields are dependent on the sputtering temperature of [TiN/NiFe]5 multilayers: once sign change for FePt/[TiN/NiFe]5 RT and three sign changes for FePt/[TiN/NiFe]5 HT. Simultaneously, when the magnetization direction of NiFe changes from the Hx direction to −Hx direction, the switching polarities at Hx = 0 always remain unchanged, which is different from other groups’ reports. These phenomena may be attributed to the combined effect of TiN layer thickness induced ferromagnetic or antiferromagnetic coupling and the inherent Hin. Furthermore, gradual tuning of resistance states through the trains of current pulses has also been realized, showing potential applications in artificial synaptic networks. These results will put forward the applications of L10-FePt in current controlled MRAM and neuromorphic computing.

Volumetric and areal capacitance are as important as gravimetric capacitance for small energy storage devices. However, achieving both a high volumetric and a high areal capacitance is still a big challenge. Here we report a dense redox organic molecules/graphene network, in which highly redox active sodium anthraquinone-2-sulfonate (AQS) molecules are anchored on interconnected and highly conductive graphene sheets by noncovalent π–π interactions to form high-performance supercapacitors (SCs). The AQS/graphene (AQS/G) has a high volumetric specific capacitance of up to 650 F cm−3 and an excellent rate capability (422 F cm−3 even at 30 A g−1), as well as a good cycling stability. A maximum areal specific capacitance of 13.3 F cm−2 is achieved at a high mass loading of 32 mg cm−2 (200 μm in thickness), which is amongst the highest values recorded for organic-based materials for SCs. An asymmetric SC constructed with AQS/G and RuO2/graphene delivers a maximum volumetric energy density of 44 W h L−1. This outstanding performance is attributed to the excellent electron conduction and ion transport provided by the dense but interconnected graphene network. This work suggests a new way for organic-based high-performance electrode materials to be used in electrochemical energy storage devices.

In the present work, the structural, magnetic and electronic properties of a novel one-dimensional infinite monatomic copper wire (1D-IMCW) have been investigated using first-principles computational calculation. Geometrical optimization shows that a minor difference in energy will lead to a transformation happening between a non-magnetic configuration and a magnetic configuration with the condition of a weak magnetic field. Notably, ferromagnetic 1D-IMCW can be used as a half-metal according to the calculated results of its band structure and density of states. Furthermore, it is discovered that this nanowire exhibits excellent optical properties, i.e. strong absorption across the visible range.

Two-photon photodynamic therapy (TP-PDT) plays crucial roles in curing tumors because it involves deep penetration of drugs into the tissue and has minimal damage to the surrounding cells. Our theoretical study was aimed at providing fresh insights into photosensitizers, such as [Ir(N^C)2(N^N)]+ (N^C = 2-phenylpyridine, N^N = bis-benzimidazole) and [Rh(N^C)2(N^N)]+, to treat cancer via the TP-PDT route. To better understand the properties of the complexes [Ir(N^C)2(N^N)]+ and [Rh(N^C)2(N^N)]+, the one-photon and two-photon absorption electronic spectra, energy gap (ΔES-T), strength of two-photon absorption cross-section (δ), spin-orbit matrix element (S1|ĤSO|Tj), and phosphorescence lifetimes (τ) were calculated by DFT and TD-DFT. The calculation results suggested that both complexes met the criteria (i.e. an efficient ISC process, enough energy to produce 1O2 and phototherapeutic window of the absorption wavelength) of photosensitizers; importantly, the designed complex [Rh(N^C)2(N^N)]+ had better performance than [Ir(N^C)2(N^N)]+, especially in the long-lived triplet excited state. It is expected that our research can make quite a few contributions to the development of photosensitizers and establish some guidelines for experiments based on TP-PDT.

Solvent recovery is a big challenge in conventional solution electrospinning for the large-scale production of ultrafine fibers because the precursor utilization ratio is usually less than 20 wt%. In this paper, we report an eco-friendly two-component electrospinning technique for the fabrication of acrylate composite fibers using a homemade device at room temperature. During this electrospinning process, the two-component spinning solutions (component A: t-butyl peroxy-2-ethyl hexanoate (BPOEH), isobornyl methacrylate (IBOMA), nitrile rubber (NBR), methacrylic acid (MAA); component B: N,N-dimethylaniline (DMA), IBOMA, NBR and MAA) are nearly all electrospun into ultrafine fibers, and the utilization ratio of the precursor can reach more than 90 wt%. The fiber solidification mechanism can be ascribed to the rapid polymerization of the IBOMA monomer in the presence of free radicals formed by a redox initiation system (BPOEH + DMA), which is different from the solvent evaporation in solution electrospinning or cooling solidification in melt electrospinning. Such a two-component electrospinning technique may stimulate the development of an eco-friendly approach to fabricate composite and functional ultrafine fibers.

Sulfur-functionalized graphene monoliths with a high sulfur fraction (16.8 wt%) were prepared to demonstrate a high capacity (∼400 mA h g-1 at 0.1 A g-1) and ultrafast (∼120 mA h g-1 at 5 A g-1) sodium ion storage. The reversible reaction of -C-Sx-C- with sodium ions contributes to the extra capacity while a 3D graphene network guarantees high rate capability.

Trimethylamine N-oxide (TMAO), which is oxidized from trimethylamine (TMA) by hepatic flavin-containing monooxygenases (FMOs), promotes the development of atherosclerosis and is a new target for the prevention and treatment of cardiovascular disease from the perspective of intestinal flora. TMA is transformed by intestinal flora from TMA-containing nutrients, such as choline. Some small molecular agents lower serum TMAO and/or cecal TMA levels. However, probiotics that can effectively reduce serum TMAO levels are currently lacking. In this work, five potentially probiotic strains were administered to mice supplemented with 1.3% choline. Only Lactobacillus plantarum ZDY04 significantly reduced serum TMAO and cecal TMA levels by modulating the relative abundance of the families Lachnospiraceae, Erysipelotrichaceae and Bacteroidaceae and the genus Mucispirillum in mice and not by influencing the expression levels of hepatic FMO3 and metabolizing choline, TMA, and TMAO. In addition, L. plantarum ZDY04 can significantly inhibit the development of TMAO-induced atherosclerosis in ApoE-/- 1.3% choline-fed mice as compared with the untreated PBS group. In conclusion, the use of L. plantarum ZDY04 may be an alternative approach to reduce serum TMAO levels and TMAO-induced atherosclerosis in mice.

A dissipative particle dynamics (DPD) simulation is performed to investigate the spontaneous onion shape vesicle formation and fusion of A6(B2)3 type comb-like block copolymers with a semiflexible hydrophobic backbone. Our results show that comb-like block copolymers of A6(B2)3 type may be a good candidate for onion shape vesicle formation. The spontaneous fusion dynamics between the onion shape vesicles is studied, and the fusion process can be characterized as having two parts: outer and inner membrane fusion. However, both parts have similar fusion dynamics which coincide with that observed in vesicles formed of linear diblock copolymers. In addition, the mixed systems containing amphipathic linear and comb-like block copolymers are investigated in dilute solution. By systemically varying the amount of linear block copolymers and the bond angle potential of the hydrophobic blocks, we construct a diagram to indicate the thermodynamically stable region, in which irregular vesicles, tubular vesicles, spherical vesicles, rod-like and toroidal micelles are observed. Nevertheless, no difference in the vesicle fusion dynamics is found. The main reason may be attributed to the molecular structures which possess the same hydrophobic but different hydrophilic block.

In this paper, a rationally designed low temperature and surfactant-free ion-exchange strategy to synthesize monodisperse hexagonal NaGdF4 nanorods from a layered gadolinium hydroxynitrate precursor is reported for the first time. This novel synthetic process takes advantage of the structural similarity between the precursor and the hexagonal NaGdF4 to avoid the formation of the kinetically favored cubic phase. The formation mechanisms were discussed in detail by tracking the phase and morphology evolution during the reaction process. In addition, the downconversion and upconversion properties were investigated under laser excitation, and the products exhibited intense characteristic luminescence.

To overcome tough conditions currently used for the preparation of nanostructured hematite films on a conducting substrate, a rational and easy method of chemical etching involving Fe3+ release and material growth in the presence of OH− has been developed. By carefully tuning the parameters influencing the morphologies of hematite, including the synthetic procedure, the concentration of etching solution, temperature, etching time and the morphology controlling surfactant, hematite films grown on iron foil with various morphologies (e.g. nanorod, nanowire, ultrathin nanoflake and cauliflower-like shape) have been achieved. In particular, it is found that F− is an effective surfactant to control the morphology as well as the crystallization process of hematite. Ultrathin nanoflakes having a minimized feature size exhibit the best photocurrent of 0.5 mA cm−2 (1.23 V vs. RHE, RHE is reversible hydrogen electrode) among the samples tested as a result of facilitated hole diffusion to the electrolyte and thus lowered carrier recombination. Compared with pristine hematite, a nearly tripled photocurrent is observed when H2O2 is added in the electrolyte as a hole scavenger, suggesting the presence of a charge injection barrier in the surface of samples. According to this, the strategy of Co2+ treatment is utilized and the improved photocurrent is seen, likely due to the improved water oxidation kinetics and surface state passivation. We believe that this convenient and economical method can be extended to the synthesis of other alkaline metal oxide nanomaterials as long as the redox potential of S2O82−/SO42− is higher than Mn+/M (M refers to metal).

A controllable drying strategy is proposed for the precise and non-destructive control over the structure of a 3D graphene assembly. Such an assembly is used as a model carbon material to investigate the pore structure-dependent shuttle effect and cycling performance of the cathode of a Li-S battery.

Compact energy storage with high volumetric performance is highly important. However, the state-of-the-art electrodes and devices remain far from the requirements due to the lack of consideration from a device perspective, which not only demands a high specific gravimetric capacity, but also needs to take into account operation voltage, material density and electrode thickness. We develop a novel approach to fabricate a monolithic ultra-thick and dense carbon electrode for symmetric supercapacitors, starting with graphene assembly and taking all the above factors into consideration. We found that zinc chloride is an ideal sacrificial pore former, and taken together with capillary drying can tune the specific surface area of the monolithic graphene from 370 to over 1000 m2 g−1 while the monoliths maintain a high density from 1.6 to 0.6 g cm−3. Having a good balance of porosity and density, the directly sliced graphene pellet electrode with a thickness up to 400 μm delivers a capacitance of 150 F cm−3 in an ionic liquid electrolyte, corresponding to a volumetric energy density of ∼65 W h L−1 for a symmetrical supercapacitor device, the highest value reported to date for supercapacitors. This study presents a design principle for electrode materials towards next-generation energy storage devices, not limited to supercapacitors, which are becoming smaller, lighter but more energetic.

This work reports the first example of boron-doped lithium clusters, BLin, activating CO2. The investigation shows that a kind of novel BLin–CO2 (n = 2–6) complex (In) with bidentate double oxygen M(η2-O2C) coordination is obtained through the bimetal 2Li of BLin clusters binding to the two O atoms of CO2, and the structural integrities of BLin clusters are not destroyed. We find that the partial negative charge transfer from BLin to the π* orbital of CO2 leads to weakening of the CO bonds of CO2 and an active CO2 moiety, except for when n = 2. Further, we perform reactions between In (n = 3–6) and benzene to elucidate a novel alternative approach to direct carboxylation by inserting CO2 into C–H bonds. We find that the carboxylation of the C–H bond of benzene can be achieved through the transition states (TS) of C–C bond formation and H-atom-transfer from C to O via two H2O molecules acting as a H-transfer tunnel. Comparing the transition states of H-direct transfer and one H2O molecule assisting H transfer, two H2O molecules assisting H-transfer as a tunnel is shown to lower the barrier, due to this long H-bond bridge effectively easing the rotation of the dihedral angle between the C6H6 and CO2 moiety planes. Considering the whole free energy profile, BLi5 and BLi6 clusters are more feasible for the carboxylation of C–H bonds.

The volumetric performance of electrochemical energy storage (EES) devices, other than gravimetric performance, is attracting increasing attention due to the fast development of electric vehicles and smart devices. Carbon-based electrodes have advanced the fast development of EES devices while being limited by their low volumetric performance because of their porous structure and the resulting low density. This paper aims to clarify the importance of the volumetric performance and review the most recent progress in advanced EES devices with a high volumetric performance. Strategies for improving the volumetric performance, particularly with carbon-based materials, are also proposed here. The transformation of normal low-density carbons to high-density ones through the assembly of different building blocks is highlighted as a promising remedy for this issue, and their applications in next-generation EES devices (Li–S, Li–air, Na-ion, etc.) are also discussed.

This work presents a new class of porous graphene particles with a three-dimensional microscale network and an ultrahigh specific surface area (2590 m(2) g(-1)), which is obtained by the KOH activation of a compact graphene hydrogel. As supercapacitor electrodes, such porous graphene particles show high compressibility and little capacitance loss when subjected to a compressive force up to 40 MPa, yielding an excellent volumetric performance with an ionic liquid electrolyte. Such carbon materials show great promise for applications needing high volumetric energy.

Water-soluble CuInSe2/ZnS (CISe/ZnS) and AgInSe2/ZnS (AISe/ZnS) core/shell quantum dots (QDs) on a multigram scale have been synthesized by using gelatin and thioglycolic acid as dual stabilizers in an electric pressure cooker. The core/shell QDs present composition-tunable emission in the range of 582 nm to 686 nm with a maximum PLQY of 23.3%. The core/shell QDs also exhibit good water/buffer stability. The red-emitting CISe/ZnS QDs are applied as wavelength converters to achieve warm white light-emitting diodes.

Monodisperse polyhedral nickel nanoparticles composed of small nanocrystals have been successfully synthesized by a facile poly(N-vinyl-2-pyrrolidone) (PVP) mediated solution reduction process with hydrazine hydrate as the reducing agent. The phase structure, morphology and magnetic properties of the as-prepared products were extensively characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and vibrating sample magnetometer (VSM). XRD pattern indicated that the as-synthesized products were nickel with well-crystallized face-centered cubic structure. SEM and TEM observations showed that the polyhedral nanoparticles consist of nanocrystals with size around 2 nm. The formation of these polyhedral nanoparticles is attributed to the oriented aggregation of nickel nanocrystals around a polymer-Ni2+ complex framework structure. The magnetic property investigation shows that the polyhedral nickel nanoparticles exhibit a ferromagnetic behavior and possess a higher coercive field value than that of the bulk nickel.

Graphene oxide hydrogel is used as a reactive template to prepare nanoporous materials with a 3D microstructure. The as-prepared porous MnO2 shows a capacitance retention of ~70.6% at a current density as high as 15 A g(-1), resulting from the 3D interconnected ion transport channel replicated from the graphene oxide hydrogel.

The elaboration of structurally related tetrazolate-based ligands from achiral to chiral led to the formation of two new chiral coordination polymers (CCPs). Compound 1 contains an infinite 1D zigzag Hg chain and a 1D helical water chain, its chirality is induced by the symmetry breaking of an achiral ligand while compound 2 is a 3D framework with a new 3-connected structural topology constructed from a homochiral ligand. The chiral natures of the two CCPs were both confirmed by circular dichroism (CD) spectra. The luminescent properties of compounds 1 and 2 were also investigated. Their strong luminescence suggest that both compounds may be excellent candidates as potential photoactive materials.

Free-standing graphene-based macroscopic membranes, which are characterized by a layered structure and tunable conductivity, are prepared by a self-assembly process at a liquid–air interface. Since the preliminary results indicate that it is hard to construct macroscopic graphene membranes solely by low-temperature exfoliated graphene nanosheets (LGNs) at the liquid–air interface, graphene oxide nanosheets (GONs), as the stacking template and sticking component, are introduced into the assembly process of graphene layers to promote the formation of layer-by-layer stacking structure and help form a conductive macroscopic membrane. The conductivity of such a graphene-based membrane can be tuned by changing the GON fraction in the LGN/GON hybrid membrane.

The innate character of graphene, defined as the basic unit of sp2carbon materials, provides opportunities for the design and construction of carbon nanostructures with tuned properties. Here, we report a novel three-dimensional graphene macroassembly with a core–shell structure starting from reduced graphene oxides (RGO) by a one-pot self-assembly process under very mild conditions. In the presence of KMnO4, such an assembly process is initiated by low-temperature heating below 100 °C at atmospheric pressure and is totally free from a severe hydrothermal process. Such a core–shell structure is characterized by a porous core and layered membrane shell, and the macro-morphology and infrastructure of the macroassembly are well controllable and tunable. The macroassembly presented here and its self-assembly preparation directly from graphene nanosheets present the first example of the simultaneous formation of a coaxial hybrid infrastructure in a graphene-based nanostructured material, and such a core–shell structured macroassembly shows potential for use in energy storage and other applications.

The influence of the nature of metal ions and reaction conditions on the formation of group IIB metal coordination architectures of a tetrazole ligand, 2-(1H-tetrazol-5-yl)pyrazine (HL), and the luminescent properties of some complexes have been investigated. At room temperature, the reactions of Zn(NO3)2∙6H2O (or ZnCl2) and Cd(NO3)2∙6H2O with HL gave rise to two reported complexes, [M(L)2(H2O)2] (1 and 2, Acta Crystallogr., Sect. C, 2006, 62, m614; Acta Crystallogr., Sect. E, 2006, 62, m2841), respectively. However, under hydrothermal conditions, the same reactions yield 1 and another complex, {[Cd2(L)4](H2O)0.25}n (3), respectively. In both preparation conditions mentioned above, the HL ligand reacts with Hg(OAc)2 (or HgBr2) to give complexes, [Hg(L)2]n (4), [Hg(L)2]n (5) and [Hg(L)Br]n (6) with different structures. 1 and 2 have a similar mononuclear structure and in the crystal structure such molecules are further assembled together to form a 3-D α-Pt topological framework with O–H⋯N hydrogen bonds. 4 possesses a 1-D chain structure, in which the Cd(II) center is six-coordinated, with all coordination sites being occupied by N atoms of the ligands. Furthermore, such chains are interlinked via π⋯π interactions to form a 3-D framework. 4 has a 2-D (6,3) topological structure, in which the Hg(II) center is six-coordinated to six N atoms of L, and the L ligand takes a chelating-bridging mode similar to that in 3. 5 has a 2-D (4,4) topological layer structure with the metal center being six-coordinated, and the six coordination sites are held by N atoms from four L ligands, taking different coordination modes. Moreover, such planes are generated to form a 3-D structure via two kinds of π⋯π interactions. 6 is a 2-D layer with the Hg(II) coordinating to a Br atom and three N atoms of three tetrazole rings from different L ligands. This result shows that the metal ions and reaction conditions have significant influence on the group IIB metal complexes of this multifunctional ligand, and the intramolecular/intermolecular weak interactions are likely to play important roles in the formation of such complexes, especially linking the discrete subunits or low-dimensional entities into high-dimensional frameworks. In addition, the luminescent studies of HL and 1, 2, 3 and 6 indicate that they display blue emissions with different densities in the solid state at room temperature.

The in situ solvothermal reaction of 3,4-dicyano-1,2,5-thiadiazole with MCl(2) (M = Co, Ni) and NaOH afforded two isomorphous complexes, [M2(L)2(H(2)O)2]n (L = 2,1,3-thiadiazole-4,5-dicarboxylate), which exhibit a rare non-interpenetrated (10,3)-d (utp) network topology and interesting magnetic behaviors: spin-canted antiferromagnetism for the Co(II) complex, but simple antiferromagnetic coupling for the Ni(II).