Stacked Cu1.8S nanoplatelets as counter electrode for quantum dot-sensitized solar cell

It is found that the electrocatalytic activity of Cu2-xS thin films used in quantum dot-sensitized solar cells (QDSSCs) as counter electrode (CE) for the reduction of polysulfide electrolyte depends on the surface active sulfide and disulfide species and the deficiency of Cu. The preferential bonding between Cu2+ and S2-, leading to the selective formation of a Cu1.8S stacked platelet-like morphology, is determined by the cetyl trimethyl ammonium bromide surfactant and deposition temperature; the crab-like Cu-S coordination bond formed dictates the surface area to volume ratio of the Cu1.8S thin films and their electrocatalytic activity. The Cu deficiency enhances the conductivity of the Cu1.8S thin films, which exhibit near-infrared localized surface plasmon resonance due to free carriers, and UV-vis absorption spectra show an excitonic effect due to the quantum size effect. When these Cu1.8S thin films were employed as CEs in QDSSCs, a robust photoconversion efficiency of 5.2% was obtained for the film deposited at 60 °C by a single-step chemical bath deposition method

Preparation and Characterization of Nano-size Polyreactive Blue MXR

Nanosize Polyreactive blue MXR dye was synthesized from reactive blue MXR dye in presence of potassium persulfate as catalyst. The formation of polyreactive blue MXR was indicated by colour change from blue to brown. The characterization techniques such as, Fourier transform infrared spectroscopy (FTIR), Atomic force microscopy (AFM), and X-ray diffractrometry (XRD) were used to characterize the formation of nanosize polyreactive blue MXR. The absence of asymmetric stretching of NH2 group in polymer dye FTIR spectrum confirmed the polymerization of dye was occurring. The average particle size of the polymer dye was found to be 18.11 nm according to Scherer formula.AFM analysis shows the three dimensional structure of polyreactive blue MXR