Articles in 2017

In this review, we highlight the recent progress in two rising areas: solar energy conversion through plasmon-assisted interfacial electron transfer and plasmonic nanofabrication. Localized surface plasmon resonance (LSPR) of plasmonic nanoparticles and nanostructures has attracted increasing attention because of their strong near-field enhancement by interacting with visible light. Recent studies have demonstrated the capability of such plasmonic systems in producing ‘LSPR-induced hot-electrons’ that are useful in photoenergy conversion and storage when combined with electron-accepting semiconductors. Concurrently, ‘hot-electron decay’ results in strong photothermal responses or plasmonic local heating. This heating has received renewed interest in photothermal manipulation of nanoparticles and molecules.

We have developed a phage display-based solution for breast cancer precision medicine. The patient-specific tumor-targeting peptide was first selected through in vivo biopanning. The as-selected peptide was then coupled with an anti-cancer nanomaterial drug. Enhanced nanodrug accumulation was achieved, which resulted in improved tumor killing efficacy. This study demonstrates a systematic strategy for discovering and testing patient-specific tumor targeting small molecules for cancer precision medicine.

Well-defined and stable nanomicelles (20−30 nm in diameter) were demonstrated for the first time by the self-assembly of amphiphilic brush (comb-like) cyclic and tadpole-shaped copolymers based on a poly(glycidyl ether) backbone. In particular, the brush cyclic topology formed the most compact and most stable nanomicelles with an extremely narrow (pseudo-monodisperse) size distribution, which are unattainable by other conventional means. This study provides a unique opportunity for designing advanced functional high-performance amphiphile materials for micelles and facilitating their applications in various fields.

Highly efficient voltage control of magnetic anisotropy has been demonstrated utlizing an ultrathin Ir-doped Fe layer in MgO-based magnetic tunnel junctions. Ir adoms are dispersed inside the ultrathin Fe layer through the interdiffusion process. Large spin–orbit interaction of Ir atoms having proximity-induced magnetism is attributed to the enhancement of the voltage-controlled magnetic anisotropy (VCMA) effect. High speed response of the VCMA effect was also confirmed by voltage-induced ferromagnetic resonance. The achieved properties first satisfy the required specification for the new type of magnetoresistive random access memory (MRAM) driven by voltage.

A skin-like stretchable multi-functional sensor array based on a combination of PU foam and MWCNT-PANI nanocomposite is demonstrated to simultaneously detect pressure, temperature and ammonia gas with high sensitivity. The integrated sensor array with printed liquid metal interconnections operates stably under applied strain due to its attachment to the skin and under a biaxial strain up to 50%.

Nanostructural modifications, in particular nanoparticle (NP) additions, have been shown to have great success in improving energy-related material performance. We show how an economically viable method, namely metal organic deposition, can be used to obtain tunable small size (7 nm) and high number density NPs (8 × 10²² m⁻³) while maintaining the crystallinity of the perovskite-composite cuprate superconductor film matrix. Critical current density J_c(H) measurements demonstrate that the NPs are highly effective as pinning centers, decreasing vortex motion and fluctuation effects for all temperatures, magnetic field strengths and orientations measured. Our synthesis method can be applied to other perovskite-composite materials to improve their functionality.

An accurate method, with detailed analytical equations, is developed to extract the spin–orbit (SO) effective fields through analysis of the results of harmonic Hall voltage measurements. Both the z component of the applied magnetic field (its directions, together with the axes and the Hall bars, are shown in the left figures) and the second-order perpendicular magnetic anisotropy are taken into account. The contour plots (right figures) showing the deviation (in %) from input values of the damping-like (ΔH_DL) and field-like (ΔH_FL) SO effective fields clearly demonstrate a significant improvement in the accuracy of the results obtained from the new refined method.

Iron oxides were designed to the rice-grain-shaped hollow structures with hierarchical pores and highly aligned nano/micro-structures using silk fibrous templates to impose multi-functional materials for the electrocatalysts for Li-O₂ batteries and the adsorbents of organic pollutants.

Physico-chemical properties of the cargo as well as the actual conditions during encapsulation interfere during formulation of nanoparticular cargo–carrier systems. We demonstrate altered chain conformations in the different micelles due to different cargo–carrier interactions leading to different localization of model drugs within the carrier. Finally, these changes lead to differences in pharmacokinetics and biodistribution in vivo, showing the relevance of such effects in a translational manner.

Ultrathin Bi₂Se₃-CS-RGD NSs with excellent tumor-targeting ability and potent radiosensitization efficiency are constructed for imaging-guided cancer radiotherapy. The NSs in combination with X-ray irradiation inhibit HeLa cell growth by inducing G0/G1 cycle arrest and mitochondria-mediated intrinsic cell apoptosis, inhibiting TrxR and activating downstream ROS-mediated signaling pathways. Moreover, RGD coating enables the NSs to aggregate in the tumor regions quickly enabling efficient PAI of the entire tumor to facilitate radiotherapy of cervical cancer. Taken together, this study provides an effective and safe theranostic agent for next-generation cancer radiotherapy.

A new class of self-powered and flexible biomimetic NEMS flow sensor is developed that can detect minute fluid flows with ultrahigh sensitivity. The hydrogel-VACNT structure closely mimics the mechanical and material properties of the gelatinous cupula found in many biological flow sensors. This work illustrates how such a nature-inspired design when implemented in NEMS sensor through nanofabrication enhances the sensitivity of the flow sensor.

Our work contributes to synthesize a vehicle based on lipid nanoparticles, which can effectively deliver Cas9/sgRNA-fused plasmid DNA in vitro and in vivo. This approach mediated successful transfection of Cas9/sgRNA plasmids in multiple cell lines in vitro. The vehicle carrying Cas9/sgRNA targeting PLK-1 resulted in significant down-regulation of PLK-1 protein and suppression of melanoma growth in vivo.

A novel ultra-thin-walled ZnO microtube cavity with a wall thickness of ~750 nm, supporting multiple types of optical modes, including in-tube Fabry–Perot modes, in-wall Fabry–Perot modes and wave-guided whispering gallery modes is fabricated via optical vapor supersaturated precipitation. The intensities of near-band edge and X-band emission are therefore increased at least one order of magnitude in the temperature range of 0–500 °C. The ultra-thin-walled ZnO microtube demonstrates unprecedented applications, for example, temperature-sensitive multicolor luminescence, low-threshold ultravoilet (UV) lasing and high-performance recyclable on-chip photodegradation, within one platform. It provides new opportunities to design multifunctional tailored wide bandgap semiconductor devices for a variety of optoelectronic applications in micro/nanophotonics.

A gallium-based liquid metal integrated system that combines soft electronics materials and engineering designs with advanced near-field-communication (NFC) functionality is reported. Electro-mechanical characterization of the device reveals their behaviors under large uniaxial tensile and compressive strains, as well as more complex modes of deformation. Demonstrations of these devices involve their use in monitoring of various human motions in a purely wireless fashion.

Nature-inspired from the stimuli-responsive soft material in plants, multifunctional hybrid membrane with thermo-responsiveness and conductivity is synthesized by in situ formation of conductive PPy on a PNIPAm matrix. The hybrid membrane exhibits thermo-responsive electrical properties, thermo-responsive deformability, and a thermo-responsive charge effect. This simple yet efficient platform may open a new era of stimuli-responsive hydrogels to fabricate a variety of high performance electrical, electrochemical and biomedical devices

Highly flexible transparent conductive electrode (HFTCE) heater with multilayer structure based on reduced graphene oxide (rGO), carbon nanotube (CNT) and silver nanowire (AgNW). The electrical, chemical, thermal, mechanical and tribological characteristics of the HFTCE heater based on rGO/CNT/AgNW are vastly superior to those of the single layer of AgNW coating. The rGO- and CNT-based layers effectively protect AgNW against contact sliding motion as well as bending/folding. The layers are designed to reduce shear stress induced by friction and distribute the contact pressure. The HFTCE based on rGO, CNT and AgNW was applied to a heater, verifying its outstanding ability to remove frost.

A semitransparent intelligent skin-like sensor platform based on polyaniline nanowire arrays was constructed, which can act as bionic component by simultaneously sensing tactile stimuli and detecting colorless odorless gas. The highest gauge factor demonstrated is 149, making it a remarkable candidate in strain sensing applications. Simultaneously, we demonstrate the controlled olfaction ability of the sensor with the detection of methane with high sensitivity and fast response time. These results enable the realization of multifunctional and uncorrelated sensing capabilities that will have wide range applications to augment robotics, treatment, simulate skin, health and bionic system.

Schematic illustration of Biomaterial Strategies for Controlled Growth Factor (GF) Delivery for Biomedical Applications. (a) The direct approaches for the immobilization/encapsulation of GFs to biomaterials; (b) Nanocarriers for GFs encapsulation and release; (c) GFs encapsulated nanocarriers functionalized biomaterials for tissue regeneration.

The redox half-reaction of wide bandgap silver chloride was utilised to promote the photo-emitted carriers from graphene and the photoresponsivity of the phototransistor, circumventing the limitation of semiconductor bandgap and facilitating the pronounced photoresponse to long wavelength photons far beyond the optical absorption edge of AgCl.