Improved Photoelectrochemical Cell Performance of Tin Oxide with Functionalized Multiwalled Carbon Nanotubes–Cadmium Selenide Sensitizer

Abstract

Here we report functionalized multiwalled carbon nanotubes (f-MWCNTs)-CdSe nanocrystals (NCs) as photosensitizer in photoelectrochemical cells, where f-MWCNTs were uniformly coated with CdSe NCs onto SnO2 upright standing nanosheets by using a simple electrodeposition method. The resultant blended photoanodes demonstrate extraordinary electrochemical properties including higher Stern-Volmer constant, higher absorbance, and positive quenching, etc., caused by more accessibility of CdSe NCs compared with pristine SnO2-CdSe photoanode. Atomic and weight percent changes of carbon with f-MWCNTs blending concentrations were confirmed from the energy dispersive X-ray analysis. The morphology images show a uniform coverage of CdSe NCs over f-MWCNTs forming a core-shell type structure as a blend. Compared to pristine CdSe, photoanode with f-MWCNTs demonstrated a 257% increase in overall power conversion efficiency. Obtained results were corroborated by the electrochemical impedance analysis. Higher scattering, more accessibility, and hierarchical structure of SnO2-f-MWCNTs-blend-CdSe NCs photoanode is responsible for higher (a) electron mobility (6.89 × 10(-4) to 10.89 × 10(-4) cm(2) V(-1) S(1-)), (b) diffusion length (27 × 10(-6)),

Microbial Synthesis of Chalcogenide Nanoparticles

“…The core level spectrum of Cd3d in the sludge sample, however, clearly shows that the peaks at ∼405 and ~ 412 eV (Fig. 5.5) similar to the supernatant sample ascribable to Cd3d5/2 and Cd3d3/2 agree with the core level binding energies of CdSe reported earlier (Bhande et al, 2015;Deepaa et al, 2010;Subila et al, 2013). In sludge (phase I), the Cd:Se ratio was around 1:4, which is in agreement with Fig 5.2.…”

“…The core level spectrum of Cd3d in the supernatant sample shows that the peaks at ∼405 and ~ 412 eV (Fig. 5.5) ascribable to Cd3d5/2 and Cd3d3/2 agree with the core level binding energies of CdSe reported earlier (Bhande et al, 2015;Deepaa et al, 2010;Subila et al, 2013). The Cd peaks are due to CdSe and not due to CdO is further confirmed from the fact that the corresponding O1s appeared at ~ 532 eV (Table 5.1) and not in the range of 528 -531 eV, which is normally associated with metal oxide (Deepaa et al, 2010).…”

“…The C1s core level spectrum of CdSe (Table 5.1) shows a signal at ~ 285, 287.7, 288.6 eV due to C-C/C-H, C=O and C-O structures, respectively (Bhande et al, 2015;Deepaa et al, 2010;Yuan et al, 2016). The binding energy for N 1s was centred at ~ 399.5 eV (Fig.…”

One-Dimensional Electron Transport Layers for Perovskite Solar Cells

“…In the n-i-p type architecture, an n -type ETL such as TiO 2 , ZnO, SnO 2 or WO 3 is deposited on a TCO-coated glass substrate which is then followed by perovskite deposition. Over the perovskite, a p -type hole transporting layer (typically spiro-MeOTAD) is deposited and finally a high work function metal such as gold is deposited to complete the device [30,31,32,33,34,35,36,37,38]. This n-i-p configuration is necessarily used for the formation of solar cells involving 1D-ETLs to allow for proper infiltration of the perovskite into the ETL.…”

Enhancing Performance of CdS Quantum Dot-Sensitized Solar Cells by Two-Dimensional g-C3N4 Modified TiO2 Nanorods

“…Among them, single-crystalline TiO 2 nanorod array would be one of the most desirable nanostructures for preparing photoanode of QDSSC due to its effective charge transfer property as well as excellent light harvesting ability. Inorganic semiconductors QDs such as CdS, PbS, PbSe, CdTe, CdSe, and Bi 2 S 3 have been used to assist as a sensitizer for solar devices [ 9 ]. Among them, CdS is considered to be one of the potential photovoltaic semiconductive materials for its broadly tunable bandgap.…”