We herein describe our use of a water-ethylene method to prepare a composite material consisting of platinum nanoparticles and graphene. Results obtained using XPS and XRD show that the degree of reduction of graphene was increased by the incorporation of Pt, and in addition, the increased concentration of defects was confirmed by the D/G ratio of the Raman spectra obtained. In comparison with Pt films, results obtained using CV and EIS showed that the electrocatalytic ability of the composite material was greater, and afforded a higher charge transfer rate, an improved exchange current density, and a decreased internal resistance. SEM images showed that the morphology of PtNP/ GR counter electrodes is characterized by a smooth surface, however, resulting in a lower resistance to diffusion, thereby improving the total redox reaction rate that occurs at the counter electrode. PtNP/ GR electrodes have a number of advantages over other electrodes that consist solely of graphene or Pt films, including a high rate of charge transfer, a low internal resistance, and a low resistance to diffusion. In our study, we showed that DSSCs that incorporate platinum-grafted graphene had a conversion efficiency of 6.35%, which is 20% higher than that of devices with platinized FTO.

Uniform and high-quality graphene oxide thin films were prepared using a dip-coating approach and were reduced to highly electrically conductive graphene nanosheet (GN) transparent conductive films (TCFs) using hydriodic acid. Silver nanowires (AgNWs), which were modified using thiophenol and exhibited a high aspect ratio and high electrical conductivity, were deposited on the surfaces of the GN TCFs through p-p interactions between the aromatic functional groups on the AgNWs and GNs to form highperformance GN/AgNW TCFs. The GN/AgNW hybrid nanomaterial films exhibited a sheet resistance of 71 U , À1 and 85% light transmittance.

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We herein describe the preparation and characterization of a phase-separated fluorinated polymethylsilsesquioxane (PMSQ), which may be used as an antireflective coating. The results of FTIR analysis showed that when PMSQ is synthesized from methyltrimethoxysilane (MTMS), it exists mostly in the form of a cage structure. Its reflectivity of normally incident light (R) may be reduced from 3.9 to 0.9% by grafting 1H,1H,2H,2H-perfluorooctyltriethoxysilane (FTES) by means of a sol–gel process. In the study described herein, the minimum reflectivity of PMSQ was lowered to less than 1% by coating it with a single layer of fluorinated polymethylsilsesquioxane, through phase segregation of PMSQ and FTES that took place during film formation. The RI of PMSQ at 550 nm was also reduced from 1.51 to 1.42 by heating at 80 °C for 30 min, a temperature suitable for substrates, such as plastics, that have low heat resistance. Wetting and adhesion to substrates were both improved by the additional grafting of tetraethoxysilane (TEOS), again by means of a sol–gel process. Results of solid-state 29Si NMR and GPC showed increases in T 3, Q 3, Q 4, and the molecular weight, which signal the effective grafting of both the TEOS and the FTES on the PMSQ. Results from energy-dispersive X-ray spectroscopy (EDX) show that the quantity of fluorine atoms at the surface of the PMSQ film increased from 0 to 22%, providing the evidence of the phase segregation within the PMSQ film. When FTES is used, we found an increase in the water contact angle from 92° to 108°, which indicated that the hydrophobicity at the PMSQ film surface increased by increasing the FTES content from 0 to 100 wt %, using the weight of MTMS as 100%.

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