Original Article in 2016

Nickel doped Li₃VO₄ nanocrystallites with high surface energy showed excellent lithium ion storage property with a capacity of 650 mAh g⁻¹ at 50 mAh g⁻¹ and excellent capacity stability as anode in lithium ion batteries. The nickel doping promoted the formation of V⁴⁺ and more amorphous in the surface of Li₃VO₄, probably resulting in higher surface energy, more nucleation sites for the phase transformation and reducing the activation energy of the redox reactions and phase transition during the Li⁺ intercalation/extraction processes.

Peculiar GaN/InGaN-based high-density nanocrystal array was demonstrated by a simple self-assembly process. The nanocrystals consist of bending InGaN nanoplates and supporting GaN nanocolumns. The nanocrystals are umbrella shaped with diameters of ∼200–700 nm; therefore, they are referred to as InGaN nanoumbrellas. An extremely wide range of photoluminescence was obtained from a small excitation diameter of ∼10 μm of the array. The result indicates that the high-density GaN/InGaN-based nanoumbrella array can be used as a source of white light without phosphors.

A new type of non-noble-metal hydrogen evolution reaction (HER) electrocatalyst based on ultrafine Mo₂C nanoparticles embedded within 3D N-doped carbon nanofiber networks was fabricated by using a cheap, green, 3D nanostructured biomass (bacterial cellulose) as precursor. It exhibits remarkable electrocatalytic HER performance from pH 0 to pH 14.

Herein, we fabricated pure poly(3-hexylthiophene) (P3HT) film with highly oriented morphology using a small-molecule 1,3,5-trichlorobenzene (TCB) as the template for polymer epitaxy with a temperature gradient crystallization process. The strong π–π conjugated interactions as well as the very close matching between the repeat distance of the thiophene units in P3HT and the repeat distance of TCB molecules have successfully induced the epitaxy process, allowing the P3HT polymer chains to lock onto the lattice of TCB, forming highly ordered P3HT chains in the direction parallel to the fiber axis. As a result, the electrical conductivity in the direction parallel to the fiber axis was significantly improved. The maximum thermoelectric power factor and ZT value at 365 K reached 62.4 μW mK^-2 and 0.1 in the parallel direction of the TCB-treated P3HT film.

A novel and effective crystalline-Si/amorphous-Si core/shell sample configuration has been devised. The malleable amorphous Si shell helped inhibit brittle fracture, provide the confinement to significantly raise the stress level, and extend the plastic flow in crystalline Si core. This enabled a real-time observation of the stress-induced crystalline-to-amorphous transition (CAT) process in Si. In situ TEM compression experiment demonstrated a direct amorphization process from the single crystalline diamond cubic Si phase, owing to the accumulation of plastic strain and profuse stacking faults. Deep insights of the CAT process have been achieved from density functional theory simulations.

A new hybrid, fabricated by incorporating molybdenum carbide (Mo₂C) nanoparticles into nitrogen-implanted three-dimensional carbon matrix (MoCN-3D), has been developed as a highly active and durable nonprecious metal electrocatalyst for HER. The porous architecture of the developed catalyst MoCN-3D can provide continuous mass transportation with a minimal diffusion resistance and thus produce effective electrocatalytic kinetics in both acidic and alkaline media.

We have rationally synthesized a binder-free and robust electrode by directly growing urchin-shaped α-MnO₂ nanostructures on porous reduced graphene oxide-coated carbon microfiber (MGC) mats and fabricated an aqueous sodium–air cell using the MGC as an air electrode to demonstrate the rechargeability of an aqueous sodium–air battery. The fabricated aqueous Na–air cell exhibited excellent rechargeability, rate capability and round-trip efficiency.

We report the synthesis of ruthenium nanocrystal-decorated vertically aligned graphene nanosheets grown on nickel foam. As an effective binder-free cathode for Li-O₂ batteries, it can significantly reduce the charge overpotential via their effects on the oxygen evolution reaction and achieve high specific capacity, leading to an enhanced electrochemical performance.

High thermoelectric figure of merit ZT of 1.5 and a high average ZT >1.0 between 300 and 850 K can be achieved for Yb-filled CoSb₃, which are superior to those of any single-element-filled skutterudite and comparable to the best in this class of materials. The long-term debate about the Yb-filling fraction limit in CoSb₃ is clarified to be ~0.29, and the excess Yb mainly forms metallic YbSb₂ precipitates. The transport properties of the x >0.35 samples with YbSb₂ precipitates are quantitatively reproduced by the Bergman’s composite theory, providing new understanding of the role of Yb in CoSb₃.

The application of a conjugated polymer with 9,10-di(1,3-dithiol-2-ylidene)-9,10-dihydroanthracene (exTTF) units as cathode and zinc as anode enables an aqueous-based hybrid organic battery. This energy storage device features ultra-high rate performance of up to a full charge in 30 s and an extended lifetime up to 10 000 cycles.

Flexible, thermally/chemically robust and high-performance transparent conducting electrode platform (c-ITO/metal NW-GFRHybrimer film) is fabricated using surface-embedded metal nanowire and crystalline indium tin oxide hybrid electrode. Highly flexible perovskite devices are fabricated on the c-ITO/metal NW-GFRHybrimer and show mechanically stable performances.

This study describes a simple one-step fabrication process of a chitosan film that has nanoscale pillars. The adhesive is laser-bonded to tissue and does not require pillar coating to enhance bonding in water. In comparison with a ‘flat’ adhesive without pillars, the nanostructured adhesive bonded significantly stronger to tissue under either stress or pressure. This adhesive combines two mechanisms for tissue bonding: one based on the nanopatterned surface that increases the adhesion strength over short distances (van der Waals and electrostatic interactions) and another based on elastic interaction with polymer chains over much longer distances.

We demonstrate that strontium titanate (Sr-Ti-O) thin films having A-site excess composition in perovskite structure deposited by pulsed laser deposition (PLD) under magnetic field show a spontaneously formed superlattice structure. The spontaneous superlattice formation mechanism is proved to be spinodal decomposition. Results show that the Sr-Ti-O thin films with spontaneously formed superlattice structure exhibit room-temperature ferroelectricity. The induced ferroelectricity is brought about by the strain along the out-of-plane direction, and is explained based on thermodynamic considerations.

Herein, we provide a simple and straightforward DNA-based radiolabeling chemistry and additional Au shell formation strategy to obtain radionuclide-embedded gold nanoparticles (RIe-AuNPs) with a high radiosensitivity and excellent in vivo stability. The migration of DCs labeled with RIe-AuNPs to draining lymph nodes was monitored very sensitively and for a long time. The biological function of DCs labeled with RIe-AuNP was not altered and it showed strong antitumor immunity. Because of densely conjugated radioisotopes in RIe-AuNPs, we could obtain strong Cerenkov optical signal comparable with that of positron emission tomography.

Photovoltaic switching in organic heptazole Schottky diode circuits is successfully implemented under dynamic illumination. Blue energetic photons generate electron–hole pairs, and instantaneous voltage of 0.3 V is produced that is multiplied by tandem diode structure. Using the photovoltaic effects, NOT, OR and AND logics are demonstrated without any electric power.

Here, authors report spin transport in dual-gated, high-mobility bilayer graphene spin valves. Their comparative study suggests that substrate and contacts are not the key limiting sources for spin relaxation, but rather it pinpoints the role of polymer residues in current devices. Spin transport in bilayer graphene is gate tunable and this allows authors to demonstrate the evidence of magnetic moments which act as spin hot spots. By taking the advantage of their novel device architecture, they demonstrate the complete suppression of the spin signal while a transport gap was induced in these spin valve devices.

A novel dual-mode magnetic Fe₃O₄ nanoclusters was developed that exhibit efficient photothermal conversion and superparamagnetism. The particles served as numerous ‘nanoheaters’ in a PCR reaction mixture while enabling effective magnetic-based macromolecular manipulation. The thermal transfer between particles and adjacent water and DNA molecules thus become extremely efficient because of molecular-level proximity and allowed rapid amplification cycle progression. The defective mitochondrial DNA from cybrid cell lines of a patient with chronic progressive external ophthalmoplegia syndrome was efficaciously quantified by fluorescence intensity detection. Our finding provides new insight into rapid and accurate quantitative DNA diagnostics for future point-of-care applications.

Performance enhancement of n-type Bi₂(TeSe)₃ is achieved by a combination of spark plasma texturing and nanostructuring techniques, which boost electrical transport properties and suppress a simultaneous increase in thermal conductivity, respectively. A maximum ZT value over 1.1 is obtained in textured n-type Bi₂Te_2.2Se_0.8 bulks, corresponding to 35% enhancement compared with the non-textured counterparts.

In this work, a new theranostics based on GdW10@BSA NCs with ultrasmall size, but versatile properties, were fabricated, which possesses not only significant CT/ MR imaging signal enhancement but also remarkable photothermal therapy (PTT)/radiotherapy (RT) therapeutic effects for tumor. Therefore, our work may open an avenue in developing other POM-based multifunctional nanomedicines with better therapeutic outcome and fewer side effects.

Electrical control of the spin degree of freedom has enabled various vital applications in modern electronic devices, ranging from magnetoelectronics and spintronics to high-frequency devices. We demonstrate a new approach to ‘write’ enhanced magnetization in a single-phase multiferroic thin film by the application of an electric field. The induced magnetization can be controlled with nanoscopic precision via the assistance of scanning probe techniques, thus offering high potential for use in multifunctional, low power consumption and green nanoelectronics.