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In this study, we controlled the growth of crystalline plane to synthesize the vertical platinum nanopelts onto fluorine doped tin oxide (FTO) glass to construct the platinum nanoroses (PtNRs) by an easy electrochemical deposition (ECD) method at room temperature in the normal atmospheric environment, and applied the PtNRs as a counter electrode (CE) for dye-sensitized solar cell (DSSC). The morphologies and crystalline nanostructures of the ECD PtNRs were examined by field emission scanning electron microscopy and the high-resolution transmission electron microscopy. The electrocatalytic properties of the ECD PtNRs were analyzed by cyclic voltammetry and electrochemical impedance spectrum. The power conversion efficiency (PCE) of the DSSC assembled with the ECD PtNRs CE was examined under the illumination of AM 1.5 (100 mWcm − 2 ). The ECD PtNRs showed well contact behavior with FTO surface and offered a large surface area to promote the redox reaction rates therefore increased the exchange current density. Due to the PtNRs showed the macroporous structure, the electrolyte can easily diffuse through the open space between the nanopelts, resulting in improved kinetics for charge-transfer processes and reduced the charge-transfer resistance. Our findings suggest that the catalytic efficiency of PtNRs with a specific crystal plane was significantly greater than that of a traditional Pt film catalyst. In combination with a N719 dye-sensitized TiO 2 working electrode and an iodine-based electrolyte, the DSSC assembled with the PtNRs CE achieved a PCE of 6.58%, almost 10% higher than that of a cell prepared with a conventional sputtering Pt film CE (6.00%). These results provide a potential strategy for electrochemical catalytic applications.

Background Galectin-3 is widely expressed in many immunocytes and epithelial cells including skin keratinocytes. Galectin-3 can regulate immunological or inflammatory processes and plays a proinflammatory role in some disease models. Galectin-3 has a role in disorders related to ultraviolet (UV) photodamage such as apoptosis, skin squamous cell carcinoma and basal cell carcinoma. However, the evidence of galectin-3 in UVB-induced skin inflammation is still limited and the underlying molecular mechanism remains elusive. Objective We aimed to investigate the effects of galectin-3 in human epidermal keratinocytes and in mice after UVB irradiation. Methods Primary human epidermal keratinocytes with galectin-3 knockdown were used as the in vitro model. ELISA, QPCR, and western blotting were applied to evaluate the released cytokine, mRNA and protein expression. Histologic analysis, measurement of erythema and transepidermal water loss (TEWL) were applied to evaluate UVB-induced skin damage in galectin-3 knockout mice. Results In UVB-irradiated human keratinocytes, galectin-3 knockdown downregulated the UVB-induced ASC crosslinking, cleavage of caspase-1, and formation of active IL-1β. Galectin-3 knockdown also decreased UVB-induced production of reactive oxygen species, p38 phosphorylation, and COX2 expression in human keratinocytes. After four days of UVB irradiation, galectin-3 knockout mice showed reduced gross erythema, histologic features of tissue inflammation, quantified levels of erythema and TEWL compared to wild type mice. The skin tissue lysate also showed less expression of active IL-1β and COX2 in galectin-3 knockout mice. Conclusion Galectin-3 may play a positive regulatory role in UVB-induced skin inflammation.

In this study, a pulsed-mode electrochemical deposition (Pulse-ECD) technique was employed to deposit platinum nanoparticles (PtNPs) on the indium tin oxide/polyethylene terephthalate (ITO/PET) substrate as a flexible counter electrode for dye-sensitized solar cells (DSSCs). The characteristic properties of the Pulse-ECD PtNPs were prepared and compared to the traditional (electron beam) Pt film. The surface morphologies of the PtNPs were examined by field emission scanning electron microscopy (FE-SEM) and the atomic force microscope (AFM). The FE-SEM results showed that our PtNPs were deposited uniformly on the ITO/PET flexible substrates via the Pulse-ECD technique. The AFM results indicated that the surface roughness of the pulsed PtNPs influenced the power conversion efficiency (PCE) of DSSCs, due to the high specific surface area of PtNPs which enhanced the catalytic activities for the reduction (I3− to I−) of redox electrolyte. In combination with a N719 dye-sensitized TiO2 working electrode and an iodine-based electrolyte, the DSSCs with the PtNPs flexible counter electrode showed a PCE of 4.3% under the illumination of AM 1.5 (100 mW cm− 2). The results demonstrated that the Pulse-ECD PtNPs are good candidate for flexible DSSCs.

Single-crystal and fern-like Pt nanorods (Pt-NR) were electrodeposited on carbon paper. The electrocatalytic activity of prepared Pt-NR electrodes, as determined by the catalyst mass activity (MA) and specific activity (SA) for the methanol oxidation reaction, are respectively 4.59 times and 10.54 times better than that of a commercial Pt-black catalyst.

Platinum nanocubes (PtNCs) were deposited onto a fluorine-doped tin oxide glass by electrochemical deposition (ECD) method and utilized as a counter electrode (CE) for dye-sensitized solar cells (DSSCs). In this study, we controlled the growth of the crystalline plane to synthesize the single-crystal PtNCs at room temperature. The morphologies and crystalline nanostructure of the ECD PtNCs were examined by field emission scanning electron microscopy and high-resolution transmission electron microscopy. The surface roughness of the ECD PtNCs was examined by atomic force microscopy. The electrochemical properties of the ECD PtNCs were analyzed by cyclic voltammetry, Tafel polarization, and electrochemical impedance spectra. The Pt loading was examined by inductively coupled plasma mass spectrometry. The DSSCs were assembled via an N719 dye-sensitized titanium dioxide working electrode, an iodine-based electrolyte, and a CE. The photoelectric conversion efficiency (PCE) of the DSSCs with the ECD PtNC CE was examined under the illumination of AM 1.5 (100 mWcm(-2)). The PtNCs in this study presented a single-crystal nanostructure that can raise the electron mobility to let up the charge-transfer impedance and promote the charge-transfer rate. In this work, the electrocatalytic mass activity (MA) of the Pt film and PtNCs was 1.508 and 4.088 mAmg(-1), respectively, and the MA of PtNCs was 2.71 times than that of the Pt film. The DSSCs with the pulse-ECD PtNC CE showed a PCE of 6.48 %, which is higher than the cell using the conventional Pt film CE (a PCE of 6.18 %). In contrast to the conventional Pt film CE which is fabricated by electron beam evaporation method, our pulse-ECD PtNCs maximized the Pt catalytic properties as a CE in DSSCs. The results demonstrated that the PtNCs played a good catalyst for iodide/triiodide redox couple reactions in the DSSCs and provided a potential strategy for electrochemical catalytic applications.