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In recent decades, the ionic current rectification (ICR) property of asymmetric nanochannels has been widely explored in applications of energy conversion, gas separation, water purification and bioanalysis/sensors. How to fabricate nanofluidic devices with a high ICR characteristic remains of critical importance to the development of nanofluidics. Herein, we fabricated an asymmetric MOFs/PAA hybrid via in situ synthesis of a zeolitic imidazole framework (ZIF-90) on porous anodic alumina (PAA) nanochannels. The introduction of asymmetric geometry and charge distribution provides the hybrid with ultrahigh ionic rectification, which can be easily measured using an electrochemical detector. This rectification mechanism is elucidated via finite element simulation, which proves that asymmetric geometry as well as the protonation and deprotonation under varied pH values dominates the ICR property. With the advantages of low cost and facile fabrication while supporting high ionic current rectification, the prepared MOFs/PAA hybrid can be considered as a significant paradigm in nanofluidic systems and has potential applications in the fields of new ionic devices and energy conversion systems.It is imperative to understand the interfacial adhesive behaviour of nanowires (NW) integrated into a nanoelectromechanical system in order to design commercialisable nanogenerators as well as ultrasensitive sensors. Currently available interfacial adhesion characterisation techniques that utilise in situ electron microscopy subject nanoscale systems to a high-vacuum, electron-irradiated environment, potentially altering their interfacial interactions. Alternatively, force-sensing techniques conducted in air do not provide visual feedback of the interface, and therefore can only indirectly deduce adhesive properties. Here, we present an interface characterisation technique that enforces ZnO NWs to remain partially delaminated on a Si substrate, and permits optical observation of their deformed condition in air. NWs are draped over a wedge and are allowed to conform to their minimum energy state. We evaluate the strain energy stored in the suspended segment of each NW by determining their deflected shape from interferometry. We show that utilising a tailored Euler-Bernoulli beam model which accounts for the tapering and irregularity of a NW is crucial for accurately evaluating their interfacial adhesion energy. A nominal energy per unit interface area value of [capital Gamma, Greek, macron]F-B,irr,taper = 51.1 ± 31.9 mJ m-2 is obtained for the ZnO NW-Si substrate interface; a magnitude lower than that found using electron microscopy, and higher than the upper-bound of the theoretically predicted van der Waals interaction energy of γvdW = 7.2 mJ m-2. This apparent discrepancy has significant implications for any nanotribological study conducted inside an electron microscope. The results also implicate electrostatic and capillary interactions as significant contributors towards a NW's adhesive behaviour during device operation.Hydrogel materials which respond to changes in temperature are widely applicable for injectable drug delivery or tissue engineering applications. Here, we report the unsual heat-induced gelation behaviour of a low molecular weight gelator based on an Fmoc-hexapeptide, Fmoc-GFFRGD. We show that Fmoc-GFFRGD forms kinetically stable fibres when mixed with divalent cations (e.g. Ca2+). Gelation of the mixture occurs upon heating of the mixture which enables electrostatic screening by the divalent cations and hydrophobic collapse of the fibres to give a self-supporting hydrogel network that shows good biocompatibility with L929 fibroblast cells. This work highlights a unique mechanism to initiate heat-induced gelation which should find opportunities as a gelation trigger for injectable hydrogels or fundamental self-assembly applications.Bismuth oxide and its derivatives are promising materials that have applications varying from catalysis to energy-storage devices. Most of these applications benefit from the creation of crystalline nanostructures. Herein, we present a simple and fast polymer-assisted precipitation method to synthesize various crystalline bismuth oxide nanomaterials, including bismuth oxide (Bi2O3) microrods, bismuth-transition metal mixed oxide (BixMyOz, M = V, Cr, Mo, or W) nanoparticles/rods, and bismuth oxyhalide (BiOX, X = Cl, Br, or I) nanoplates. All these materials are semiconductors with bandgaps in the range of 1.76-3.43 eV. This strategy can also be used to fabricate nanostructured composites (e.g., bismuth vanadate nanoparticles on BiOX nanosheets), copper oxide nanoparticles, and potentially other metal oxide nanomaterials.TiO2/SrTiO3/g-C3N4 ternary heterojunction nanofibers with a cascade energy band alignment were designed and then fabricated by a combination of electrospinning technology and gas-solid reaction. Their photocurrent responses were 1.4 and 1.8 times higher while their transient photoluminescence lifetime were about 0.75 and 0.79 times shorter than those of TiO2/g-C3N4 nanofibers and SrTiO3/g-C3N4 nanofibers, respectively. The enhanced photocurrent response, decreased lifetime, and their dramatically decreased photoluminescence intensity clearly indicated that highly efficient cascade charge transfer and separation were achieved in the ternary nanofibers with the gradient energy band alignment compared with the corresponding traditional binary nanofibers noted above. When tested in photocatalytic reduction reactions of H2 evolution and nitrogen fixation, the corresponding reaction rates under simulated sunlight irradiation values of 1304 μmol g-1 h-1 and 2192 μmol g-1 h-1 L-1 were 2.1 and 1.9 times better than those of TiO2/g-C3N4 nanofibers and 4.2 and 3.3 times better than those of SrTiO3/g-C3N4 nanofibers, respectively. Selleckchem AZD1208 Furthermore, the photocatalytic activities of the TiO2/SrTiO3/g-C3N4 nanofibers had no significant decrease after several cycles, indicating that they possessed good structural stability properties. This work provides a new route to design and fabricate an efficient photocatalyst for photocatalytic reduction reactions.