Noble metal-free counter electrodes utilizing Cu₂ZnSnS₄loaded with MoS₂for efficient solar cells based on ZnO nanowires co-sensitized with CuInS₂–CdSe quantum dots

Abstract

Noble metal-free counter electrode using a co-catalytic loading of MoS2 nanosheets to Cu2ZnSnS4 microspheres are investigated by means of CuInS2-CdSe quantum dot (QD) co-sensitized solar cells fabricated with single crystalline ZnO nanowires. An ex situ electrophoretic deposition route is employed to deposit QDs onto ZnO nanowires that are epitaxially grown on ZnO seed layered FTO substrates. Hydrothermally grown ZnO nanowires have also established an excellent stability against the bias conditions applied to fabricate the photoanodes of the devcies. The superior photovoltaic performance of CuInS2-CdSe QD co-sensitized cells are compared with that of bare CuInS2 and CdSe counterparts, using current-voltage and incident photon-to-current conversion efficiency measurements. The present study also demonstrates an enhanced performance of the devices fabricated with 1.0 wt % of MoS2 loaded Cu2ZnSnS4 basaed counter electrodes in contrast to bare Cu2ZnSnS4. Hydrothermal loading of MoS2 to Cu2ZnSnS4 generates an electrically interconnected network of Cu2ZnSnS4 microspheres, leading to a facile charge transport in the counter electrode of the devices. MoS2 in its nanosheet form acts as an electrical bridge that interlinks the Cu2ZnSnS4 microspheres. Additionally, a favorable band energy alignment of Cu2ZnSnS4 and MoS2 stimulates the charge transfer dynamics in Cu2ZnSnS4-MoS2 composite. Electron transport and recombination kinetics of the devices are measured using electrochemical impedance spectroscopy.devices revealed an additional benefit of direct 1D electrical

Quantum dot-sensitized solar cells

“…(CZTSe) [373][374][375][376][377][378][379] 399 Choi and coworkers prepared carbon dot-Au nanoraspberries CE, exhibiting high electrocatalytic activity, lower charger-transfer resistance, and larger exchange current density than the reference Au CE and obtained a PCE of 5.4%. 329 Bhattacharyya and coworkers reported a composite CE containing microwave synthesized CuxS and graphene oxide nanoribbon (GOR) for QDSCs.…”

Construction of Bi2S3/TiO2/MoS2 S‐Scheme Heterostructure with a Switchable Charge Migration Pathway for Selective CO2 Reduction

“…χ values are 5.3, 5.8, and 5.32 eV for Bi 2 S 3 , TiO 2 , and MoS 2, respectively. [ 52–54 ] CBM and VBM values were found to be 0.06 and 1.54 V for Bi 2 S 3 , −0.305 and 2.905 V for TiO 2 , and 0.09 and 1.55 V for MoS 2 . However, the VBM was further confirmed experimentally by valence band XPS (VB‐XPS) for all the pristine semiconductors (Figure 4b–d).…”

Miniaturization of transition metal hydroxides to hydroxide dots: A direction to realize giant cyclic stability and electrochemical performance

“…These bandgap values permitted that the developed metal hydroxide size is undoubtedly a quantum dot confinement region. 57 The detailed explanation of various chemical states and binding energy (BE) of composites materials were studied using X-ray photoelectron spectroscopy (XPS) measurement of fabricated electrode CN 1:1. As shown in Figure 3A 2+ , and Ni 3+ in the developed electrode materials constructed the platform for more electroactive sites for ions rapid movement in the redox Faradic charge transfer, which improved the overall performance of electrochemical properties.…”