Current density enhancement in ZnO/CdSe photoelectrochemical cells in the presence of a charge separating SnO2 nanoparticles interfacing-layer

Abstract

Photoelectrochemical cells (PECs) of ZnO/CdSe decorated with a charge separating SnO2 nanoparticles (NPs) layer of various thicknesses are prepared and characterized by using scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS), UV-visible absorption, energy dispersive X-ray analysis spectroscopy (EDX) and incident photon-to-current conversion efficiency (IPCE) measurements. A uniform coverage of the SnO2 NPs layer over ZnO/CdSe electrode surface is evidenced. The EDX elemental mapping analysis of the ZnO/CdSe/SnO2 PECs demonstrates the presence of Sn and O over the surface. A remarkable improvement in the light harvesting efficiency confirmed from the IPCE measurement, supports an enhancement in current density in the current density-voltage measurement due to increased electron transport and smaller charge recombination. Moreover, these observations are corroborated with the EIS measurement as a cell with SnO2 reveals a reduced charge transfer resistance due to which the power conversion efficiency is increased from 2.20 to 3.41% i.e. 55% compared to the pristine ZnO/CdSe PEC.

Photonic sintering of a ZnO nanosheet photoanode using flash white light combined with deep UV irradiation for dye-sensitized solar cells

“…The important advantage of photonic sintering is that it eliminates the need for heating at high temperature, which not only reduces the fabrication time, but also allows the use of inexpensive plastic substrates applicable in exible electronics. [62][63][64][65] In order to show that our photonic-sintered ZnO NSs led to the improved charge transfer characteristics of the dye cell, we conducted electrochemical impedance spectroscopy (EIS) measurements. The equivalent circuit used for the EIS measurements and the extracted EIS electronic parameters are presented in the ESI in Fig.…”

“…Considering these limitations of the conventional sintering process, the development of a novel sintering technique that is suitable for all types of solar cells is highly desired but it is still challenging to achieve a better PCE swily and efficiently without damaging the nanostructures and heat-sensitive substrates. 24 In recent years, several researchers have demonstrated that ash white light (FWL), [25][26][27][28][29][30] UV irradiation, 31 microwave irradiation, 32 laser sintering [33][34][35] and IR sintering 36 can be used for sintering a metal oxide and Cu-nanolinks and for the fabrication of TiO 2 as well as for counter electrode development. Among these, FWL-based sintering is essentially a sintering technique, which, in contrast to conventional oven sintering, employs the heat generated locally by the absorption of visible light in the target material to achieve the necessary temperature for sintering the material.…”

Large area growth of MoTe2 films as high performance counter electrodes for dye-sensitized solar cells

“…DSSCs were fabricated to evaluate the CE performance of the MoTe 2 films using our method 38 – 41 . Briefly, thin blocking layer TiO 2 was deposited onto a cleaned FTO glass substrate (15 × 15 mm 2 ) by dipping it in 40 mM TiCl 4 solution for 30 min at 70 °C and annealing it at 450 °C for 30 min.…”

Quantum dot sensitized solar cell: Recent advances and future perspectives in photoanode

“…Layer of SnO 2 nanoparticles over the ZnO/CdS photoanode enhances electron transportation and suppress charge recombination resulting into 55% increased PCE limited to 3.41% compared to bare ZNO/CdS based solar cell [99].…”