Indium Sulfide Based Photoelectrodes for All-Vanadium Photoelectrochemical Redox Flow Batteries

The utilization of indium sulfide (In2S3) photo-electrodes in an all-vanadium photoelectrochemical redox flow battery system has been investigated. The In2S3-based photo-electrodes have been prepared via the ultrasonic spray pyrolysis (USP) method. The thickness of the In2S3 photoelectrodes has been altered via increasing the pass number of the USP nozzle from 25 to 75 passes. Each pass delivers 6 mu L.cm(-2) of the precursor solution. Within the scope of the photoelectrochemical oxidation on the In2S3, the vanadium couples of VO2+/V3+ have been proven to be promising redox species. The maximum charge separation and quantum efficiencies of 46% and 20% have been calculated, respectively

Author Correction: Photo-supercapacitors based on nanoscaled ZnO (Scientific Reports, (2022), 12, 1, (11487), 10.1038/s41598-022-15180-z)

Correction to: Scientific Reports, published online 07 July 2022 The original version of this Article contained an error in the Acknowledgements section. “I.I. acknowledges the partial financial support from the SONATA BIS project 2020/38/E/ST5/00176.” now reads: “I.I. was partly funded by the NCN SONATA-BIS Program (UMO-2020/38/E/ST5/00176).” The original Article has been corrected

Photo-supercapacitors based on nanoscaled ZnO

Abstract In this study, zinc oxide (ZnO) powders in two different morphologies, nanowire (NW) and nanoflower (NF), have been synthesized by the hydrothermal method. The eligibility of the pristine ZnO nanopowders as a photo-active material has been revealed by designing P-SC devices via the facile drop-casting method on both glass and plastic substrates in large-area applications. The impact of physical properties and especially defect structures on photo-supercapacitor (P-SC) performance have been explored. Although the dark Coulombic efficiency (CE%) of both NW and NF-based P-SC were very close to each other, the CE% of NW P-SC increased 3 times, while the CE% of NF P-SC increased 1.7 times under the UV-light. This is because the charge carriers produced under light excitation, extend the discharge time, and as confirmed by electron paramagnetic resonance, photoluminescence, and transmission electron microscopy analyses, the performance of P-SCs made from NF powders was relatively low compared to those produced from NW due to the high core defects in NF powders. The energy density of 78.1 mWh kg−1 obtained for NF-based P-SCs is very promising, and the capacitance retention value of almost 100% for 3000 cycles showed that the P-SCs produced from these materials were entirely stable. Compared to the literature, the P-SCs we propose in this study are essential for new generation energy storage systems, thanks to their ease of design, adaptability to mass production for large-area applications, and their ability to store more energy under illumination

Highly efficient 3D-ZnO nanosheet photoelectrodes for solar-driven water splitting: Chalcogenide nanoparticle sensitization and mathematical modeling

Three-dimensional (3D) zinc oxide nanosheets (ZnO-NS), assembled on the FTO coated glass substrates after chemical treatment, have been achieved via a simple yet effective chemical bath deposition technique. The exploration of chalcogenide nanoparticle sensitization on ZnO-NS thin-film photoanodes led us to a spectacular enhancement in the photoelectrochemical conversion efficiency for solar-driven water splitting process as compared to the bare 3D-ZnO-NS. The maximum incident photon-to-charge carrier efficiency of bare 3D-ZnO-NS has been enhanced by approximately four folds as a result of cadmium sulfide (CdS) and cadmium selenide (CdSe) sensitization and the efficiency value have reached to 51% at 550 nm. Besides, the maximum charge injection and charge separation efficiencies of the ZnO eCdSe electrodes have been calculated as 93% and 64%, respectively. Numerical examination of the optical absorption and electrical field distribution has been performed via the finite-difference time-domain (FDTD) method in order to investigate the basis of the enhancement in the photoelectrochemical efficiencies of the 3D-ZnO-NS photoelectrodes. FDTD numerical simulation proved that the accumulation of rectangular 2D-nanosheets of ZnO in 3D-microspherical forms enhanced the light absorption significantly. Moreover, FDTD results also verified that the optical absorption of the ZnO electrodes has been extended from ultraviolet to visible region via CdS and CdSe nanoparticle deposition. (c) 2020 Elsevier B.V. All rights reserved

Zinc Oxide and Metal Halide Perovskite Nanostructures Having Tunable Morphologies Grown by Nanosecond Laser Ablation for Light-Emitting Devices

This work reports a one-pot chemical bath deposition (CBD) method for the preparation of selectively grown, morphology-tunable zinc oxide (ZnO) nanostructures provided via straightforward nanosecond fiber laser ablation. Nanosecond fiber laser ablation is different from lithographic methods due to its simple, time saving, and efficient film scribing abilities. Here, multiple morphologies of the ZnO nanostructures on the same substrate have been grown via laser ablation of the ZnO seeding layer. Selective and controlled ablation of the titanium layer, ZnO growth inhibitor, resulted in systematic growth of nanorod arrays, while the application of extensive fluence energies resulted in the penetration of the laser beam until the glass substrate induced the nanoflake growth within the same CBD environment. The laser penetration depth has been numerically investigated via COMSOL Multiphysics heat module simulations, and the optical variations between two nanostructures (nanorod and nanoflake) have been examined via Lumerical FDTD. The simultaneous growth of two morphologies served as an efficient tool for the enhancement of photoluminescence intensities. It increased the average charge carrier lifetimes of the thin films from approximately 2.01 to 9.07 ns under the same excitation wavelengths. The amplification in PL performances has been accomplished via the capstone of all-inorganic halide perovskite (IHP) deposition that brought a successful conclusion to lifetime responses, which have been increased by 1.4-fold. The development of IHP sensitized nanoscaled multimorphological ZnO thin films can, therefore, be used as potential nanomaterials for light-emitting-device applications

Efficiency enhancement in photoelectrochemical water splitting: defect passivation and boosted charge transfer kinetics of zinc oxide nanostructures via chalcopyrite/chalcogenide mix sensitization

ZnO thin films in nanorod (NR) and nanoflower (NF) morphologies were used as photoelectrode scaffolds for efficient visible-light-driven photoelectrochemical (PEC) water splitting process, where their decoration with copper indium gallium sulfide (CIGS) and indium sulfide (In2S3) layers resulted in significant PEC performance enhancement. ZnO NF/CIGS/In2S3 photoelectrodes exhibited a remarkably high PEC efficiency (∼6.0% applied bias photon-to-current efficiency, 83% incident photon-to-current efficiency) due to the negligible dark current, while ZnO NR/CIGS/In2S3 generated a photocurrent density of 30.0mA.cm-2 at 0.4 V (vs Ag/AgCl), being one of the highest performances reported in the literature for copper-based chalcopyrite photoelectrodes so far. The interfacial photoelectrode-electrolyte charge transport dynamics, investigated via intensity-modulated photocurrent spectroscopy, exhibited a sevenfold increase in charge transfer efficiencies with a significant drop in surface recombination kinetics for ZnO NF after CIGS/In2S3 decoration. The obtained results show consistency with numerically modeled electric field distribution profiles and electron paramagnetic resonance results of ZnO NF, rationalizing the enhanced charge transfer rates for decorated samples and confirming the defect passivating nature of CIGS/In2S3