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In this paper, one-step preparation of graphene/gold nanoparticle hydrogel film through the hydrothermal method is reported. The hydrogel film could be formed on a glass substrate under hydrothermal conditions, and upon freeze-drying, the aerogel film of 40 μm thickness with satisfying flexibility and strength is obtained. The aerogel composite film is characterized by scanning/transmission electron microscopy, X-ray diffraction, Raman spectroscopy and X-ray photoelectron spectroscopy. Moreover, the aerogel film is directly used as the electrochemical electrode for sensing H2O2, and exhibits good performance with a broad linear range, low detection limit and excellent selectivity. This work provides a route for the fabrication of graphene film material with wide potential in various aspects.

In this paper, one-step preparation of graphene/gold nanoparticle hydrogel film through the hydrothermal method is reported. The hydrogel film could be formed on a glass substrate under hydrothermal conditions, and upon freeze-drying, the aerogel film of 40 μm thickness with satisfying flexibility and strength is obtained. The aerogel composite film is characterized by scanning/transmission electron microscopy, X-ray diffraction, Raman spectroscopy and X-ray photoelectron spectroscopy. Moreover, the aerogel film is directly used as the electrochemical electrode for sensing H

MWCNT/octadecylamine hybrids with interesting structures were prepared via a simple ultrasonication and drip-drying method. The morphologies of the hybrids vary from lamellae, balls, to rose-like nanoflowers, depending on the weight ratio of the two components, which could be attributed to the introduction of nanotubes into the long-chained amine with self-organization characteristics. The paper chip sensor based on MWCNT/octadecylamine hybrid shows rapid response, high sensitivity and excellent repeatability to some volatile organic compounds, especially chloroform gas. The proposed sensing mechanism of the hybrid is via the swelling of octadecylamine upon the adsorption of organic gas, thus enlarging the nanotube distance in the MWCNT/octadecylamine hybrid and leading to the conductivity decrease of the paper chip.

Organic–inorganic hybrid perovskite solar cells have achieved great success in recent years. Meanwhile, inverted structured device is an important branch in perovskite photovoltaics owing to its peculiar advantages of low-temperature fabrication process and non-hysteresis behavior. In this kind of device, the electron transport material, as well as the interface between perovskite and electron transport layer (ETL), plays a crucial role in photoelectric conversion process. We report that the utilization of the fullerene derivative blend, PCBM and its dumb-belled dimer, as electron transport material in inverted perovskite solar cells, which could significantly enhance the photovoltaic performances. The morphology of ETL can be regulated by changing the admixing ratio of PCBM and its dimer. Moreover, the steady-state/time-resolved fluorescence and transient photovoltage decay measurements indicate that the optimization of perovskite/ETL interface through an appropriate fullerene blend is beneficial to promote charge separation and suppress charge recombination.

We report the in situ reduction and incorporation of gold nanoparticles into graphene oxide/polyethyleneimine composites with polyethyleneimine acting as the reducing and protecting agent for the gold nanoparticles. The resulting composites with porous structure are obtained through a simple freeze-drying method with the gold nanoparticles uniformly distributed on the graphene oxide sheets. The morphology and composition of the composite are characterized by scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction and Raman spectroscopy. The catalytic test indicates that the as-prepared porous gold nanoparticle-embedded composite catalyst could efficiently activate the reduction of 4-nitrophenol to 4-aminophenol. The recycling measurement reveals that the activity of the recovered catalyst decreases a little, mainly due to the restacking of the graphene sheets. Moreover, the porous composites used as packing material in chromatography column and injection syringe exhibit good catalytic performances in the rapid reduction of 4-nitrophenol, implying the potential applications of such porous heterogeneous catalysts in continuous catalytic reaction.

Amorphous InGaZnO (a-IGZO) thin films have been grown on polyethylene terephthalate (PET) substrates using a plasma-assisted pulsed laser deposition (PLD) technique, and a flexible ultraviolet (UV) photodetector (PD) with a simple metal–semiconductor–metal (MSM) structure was prepared on the a-IGZO films. The flexible PD shows relatively good photoresponse characteristics before and after bending, and retains good folding reproducibility after repeated bending up to 500 cycles. More importantly, it shows a fast speed with response and recovery times of 0.8 ms and 2.0 ms, 33.8 ms, which are much faster than that of the reported flexible ultraviolet detectors. The devices reported in this paper provide an optimal way to realize flexible ultraviolet detectors with fast speed.

Applying magnetic nanostructures in high density magnetic data storage is hindered by a lack of suitable substrate. Using density functional theory, we explored the potentiality of graphyne as a template for nanomagnetic bits. Due to the unique porous structure of graphyne, Os atom tightly binds to the graphyne at the hollow site with an in-plane MAE of 18 meV. Through a rigid band model, we introduced the strategy to manipulate the MAE by rearrangement of d-orbitals of Os atom. A large MAE of about 48 meV was obtained for F functionalized Os@graphyne. To obtain the out-of-plane easy axis, we have considered the MAE of several transition-metal combinations. We finally identified Os–Os@graphyne as an excellent candidate for room temperature applications due to the high MAE and the structural stability.