Cuprous Sulfide@Carbon nanostructures based counter electrodes with cadmium sulfide/titania photoanode for liquid junction solar cells

A Comparative Study of the Influence of Nitrogen Content and Structural Characteristics of NiS/Nitrogen-Doped Carbon Nanocomposites on Capacitive Performances in Alkaline Medium

Supercapacitors (SCs) have been regarded as alternative electrochemical energy storage devices; however, optimizing the electrode materials to further enhance their specific energy and retain their rate capability is highly essential. Herein, the influence of nitrogen content and structural characteristics (i.e., porous and non-porous) of the NiS/nitrogen-doped carbon nanocomposites on their electrochemical performances in an alkaline electrolyte is explored. Due to their distinctive surface and the structural features of the porous carbon (A-PVP-NC), the as-synthesized NiS/A-PVP-NC nanocomposites not only reveal a high wettability with 6 M KOH electrolyte and less polarization but also exhibit remarkable rate capability (101 C/g at 1 A/g and 74 C/g at 10 A/g). Although non-porous carbon (PI-NC) possesses more nitrogen content than the A-PVP-NC, the specific capacity output from the latter at 10 A/g is 3.7 times higher than that of the NiS/PI-NC. Consequently, our findings suggest that the surface nature and porous architectures that exist in carbon materials would be significant factors affecting the electrochemical behavior of electrode materials compared to nitrogen content.

Improved light-harvesting and suppressed charge recombination by introduction of a nanograss-like SnO2 interlayer for efficient CdS quantum dot sensitized solar cells

Quantum dot sensitized solar cell (QDSSC) performance is primarily limited by the recombination of charges at the interfaces of TiO2/quantum dot (QD) sensitizer/electrolyte. Hence, blocking or suppressing the charge recombination is an essential requirement to elevate the QDSSC performance to the next level. To retard the charge recombination, herein, we propose the introduction of a SnO2 nanograss (NG) interlayer on the surface of TiO2 using the facile chemical bath deposition method. The SnO2 NG interlayer not only inhibits the interfacial recombination processes in QDSSCs but also enhances the light-harvesting capability in generating more excitons. Hence, the TiO2/SnO2 NG/CdS QDSSCs can achieve the power conversion efficiency of 3.15%, which is superior to that of a TiO2/CdS device (2.16%). Electrochemical impedance spectroscopy, open-circuit voltage decay and dark current analyses confirm that the recombination of charges at the photoanode/electrolyte interface is suppressed and the life time is improved by introducing the SnO2 NG interlayer between the TiO2 and CdS QD sensitizer.

Cu2S nanosheets for ultrashort pulse generation in the near-infrared region

2D metal chalcogenide materials have received enormous attention due to their extraordinary bio-chemical, electronic, magnetic, thermal and optical properties. Compared with the typical two-dimensional transition metal dichalcogenides (TMDs) and topological insulators, cuprous sulfide (Cu2S) has very different two-dimensional lattice structures, along with excellent electro-catalysis and high conductivity. However, the nonlinear optical properties of Cu2S have never been studied until now. Here, the nonlinear photonics characteristics of Cu2S and its application in ultrafast lasers have been systematically studied for the first time. Through optical deposition of Cu2S nanosheets on a tapered fiber, the nonlinear optical properties of Cu2S nanosheets are measured through the interaction with the evanescent field. The results indicate that superior nonlinear saturable absorption properties with a modulation depth of 0.51% are achieved. An erbium-doped fiber (EDF) laser is constructed to verify the performance of the Cu2S saturable absorber (SA). The results show that an output pulse with 8.06 MHz repetition rate, 1.04 ps pulse duration, 1530.4 nm central wavelength and 3.1 nm spectral width without an obvious Kelly sideband is obtained. Considering the diversity of the metal chalcogenide family, various engineering applications may be developed from the nonlinear saturable absorption characteristics of Cu2S, including optical fiber communication/sensing, precision optical metrology, material processing and nonlinear optics.

The enhanced photo-thermal therapy of Surface improved photoactive cadmium sulfide (CdS) quantum dots entrenched graphene oxide nanoflakes in tumor treatment

Cancer is one of the death causing disease is always being a public health concern due to its rapid increase in the world population. Hyperthermal therapy is an anticancer treatment mutually given with chemotherapy. In the present study, CdS/rGO nanocomposites were synthesized using simple and scalable solvothermal method and applied as an efficient material in anticancer treatment. The prepared nanocomposites were characterized from physicochemical characterization techniques. The surface morphology and the crystallographic details were obtained from TEM and XRD analyses respectively. The elemental composition was confirmed from XPS spectra. The phase purity and the functional group analysis were done using Raman and FTIR spectroscopies respectively. The morphological analysis has been displayed the spherical shaped CdS nanoparticles that are firmly attached on the rGO thin sheet matrix further confirmed the formation of CdS/rGO nanoflakes. The live-dead assay method (cancerous and normal cell lines) cytocompatibility study displayed the cell survival of the CdS/rGO nanomaterials exhibited that above 95%, which means materials highly appropriate for the cancer therapy. The temperature profile of the CdS/rGO nanoflakes has enhanced effectively under the NIR absorption property of CdS coated rGO nanoflakes, which influenced to the cancer cell death. The results shown the anticancer activity of the proposed nanocomposites could open a new avenue in biomedicine research and utilized as an efficient materials for practical applications.