Single-walled carbon nanotubes (SWNTs) were chemically functionalized with amphiphilic octadecylamine after purification. Lower density and highly oriented SWNTs were obtained via Langmuir–Blodgett (LB) technique. A model was introduced to explain the compression-induced alignment. The phase behavior of the spreading monolayer was studied by surface pressure-area isotherms at different temperatures and different compression speeds. The transferred LB films of SWNTs with different mean lengths were investigated by the field emission scanning electron microscopy, showing that SWNTs with average length at 1000–2000 nm have more preference of reorientation upon compression than shorter ones (∼500 nm), while SWNTs that are too long (∼3000 nm) would tangle together and the reorientation is weaker. Multilayers (up to 18 layers) of SWNTs were obtained with high transfer ratios (>0.93) and the UV-vis absorption spectra indicated that the layer-by-layer deposition was successful.

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We investigate the effects of liquid crystals (LCs) on the power conversion efficiency of dye-sensitized solar cells (DSSCs). The photovoltaic and electrochemical impedance spectra indicate that minute amounts of LC dopant decrease the short-current density of DSSCs because the doped LCs reduce the electrochemical reaction rate between DSSC counter electrode and electrolyte. The doped LCs delay the degradation rates of DSSCs because of the interaction between cyano groups of the doped LCs and organic solvent in the liquid electrolyte. Owing to the molecular interaction, the doped LCs increase the viscosity and stability, thereby inhibiting the evaporation rate of the liquid electrolyte.

Light-driven hydrogen evolution from liquid hydrogen carriers offers an innovative solution for the realization of safe storage and transportation of hydrogen. The exploration of efficient and cost-effective cocatalysts is highly desirable for constructing an affordable light-driven catalytic architecture. In this work, nickel–iron bimetal (NiFe) is rationally designed and then supported by gallium nitride nanowires (GaN NWs)/Si for light-driven hydrogen generation from methanol aqueous solution. Under optimized conditions, the H2 evolution rate of NiFe is even comparable to noble metals, e.g., Pt, Ru. By correlative operando spectroscopy characterizations, with density functional theory calculations, it is discovered that Fe is cooperative with Ni for dramatically lowering the energy barrier of the potential-limiting step of *CHO → *CO. What is more, by coordination of photoexcited charge carriers with photothermal effect, the production of hydrogen from CH3OH/H2O is evidently improved via the evolving track of *CH3O > *CH2O/*CHO > *CO > *CO2, in concurrent H2O dissociation toward ·OH. Combined with the superior optical and electronic attributes of the GaN NWs/Si semiconductor platform, NiFe bimetal enables the achievement of a marked hydrogen activity of 61.2 mmol g–1 h–1 by the only input of light under ambient conditions. This study presents a promising strategy for hydrogen release from liquid hydrogen carriers by using earth-abundant materials under mild conditions.

The authors report the suppression of the off-state leakage current and subthreshold swing (SS) in inkjet-printed poly(3-hexylthiophene) thin-film transistors with asymmetric work function source and drain electrodes. Indium tin oxide (ITO) material was used as source/drain electrodes and the source electrode was irradiated by KrF excimer laser. The dominant mechanisms for the suppressive Ioff could be attributed to the increase in the work function of ITO source irradiated by the excimer laser. Lower trap state density formed on the laser irradiated source electrode. Holes could be easily injected into the channel at small lateral electric field resulting in smaller threshold voltage and SS.