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Abstract: In this paper, we studied the influence of different cations on redox behavior of I− and I3 − by cyclic voltammetry and electrochemical impedance spectroscopy. It was demonstrated that increasing cation size tends to give rise to higher reductive activity of I− and lower diffusion coefficient of I3 − in these cations, alkylimidazolium, [Na⊂15-C-5]+ and [K⊂18-C-6]+. Moreover, we measured the performance of dye-sensitized solar cells (DSCs) with electrolyte containing [K⊂18-C-6]I or 1,2-dimethyl-3-propylimidazolium iodide (DMPII). It was found that dye-sensitized solar cells (DSCs) with [K⊂18-C-6]I give a little higher short-circuit photocurrent density and a little lower fill factor than DSCs with DMPII. [Copyright &y& Elsevier]

Abstract: Cu2ZnSnS4 (CZTS) thin films were successfully deposited using vacuum thermal evaporation from single quaternary CZTS semiconducting material powder source, followed by annealing at 300°C for 40min under high purity N2 atmosphere. X-ray diffraction (XRD) patterns indicated that as-deposited CZTS thin films transformed from amorphous state into crystalline state with kesterite structure after annealing. Energy dispersive X-ray spectroscopy (EDS) determined the compositions of the CZTS thin films were Zn-poor, Sn-rich and S-rich. Scanning electron microscope (SEM) images, ultraviolet–visible–near infrared (UV–Vis–NIR) spectra and the Hall measurements showed the annealed CZTS thin film exhibited a smooth, densely packed and homogeneous surface, a direct band gap of 1.55eV and a p-type conductivity. The fabricated photovoltaic device obtained a conversion efficiency of 0.36%, open-circuit voltage of 493mV, short-circuit current density of 1.76mA·cm−2, and fill factor of 0.42. [Copyright &y& Elsevier]

To increase the loading quantity of PbS quantum-dots, the polysulfide anion (S22−) was firstly introduced in successive ionic layer absorption and reaction process to prepare PbS quantum-dot thin films on TiO2 nanorod arrays. The influence of polysulfide anion (S22−) concentrations in the precursor solution on the deposition of PbS quantum-dot thin films was systematically investigated and the photovoltaic performance of the corresponding solid-state PbS quantum-dot sensitized solar cells with spiro-OMeTAD was evaluated. The loading quantity and crystallinity of PbS quantum-dots increased with the increase of polysulfide anion (S22−) concentrations from 0 to 1 mM and 2 mM. When the polysulfide anion (S22−) concentration was 1 mM and the surface of TiO2 nanorod arrays was modified by 3-mercaptopropionic acid, the optimal photoelectric conversion efficiency of 4.75% was achieved, along with the open-circuit voltage of 0.56 V, short-circuit photocurrent density of 13.00 mA cm−2 and fill factor of 64.8%. The photoelectric conversion efficiency of 4.75% was relatively high in solid-state PbS quantum-dot sensitized solar cells using successive ionic layer absorption and reactions.To increase the loading quantity of PbS quantum-dots, the polysulfide anion (S22−) was firstly introduced in successive ionic layer absorption and reaction process to prepare PbS quantum-dot thin films on TiO2 nanorod arrays. The optimal photoelectric conversion efficiency of 4.75% was achieved, along with the open-circuit voltage of 0.56 V, short-circuit photocurrent density of 13.00 mA cm−2 and fill factor of 64.8%. [ABSTRACT FROM AUTHOR]

Abstract: In this study, we demonstrate the preparation of novel hierarchically porous β-Ni(OH)2 microspheres constructed with nanoflakes through a simple solution-phase approach, using NiCl2·6H2O and hexamethylenetetramine (HMTA) as the starting materials without adding any additives. NiO nanoparticles with the average diameter of 10 nm were obtained by calcining the as-prepared β-Ni(OH)2 microspheres at 500 °C under ambient pressure. On the other hand, β-Ni(OH)2 nanoplates were prepared by substituting HMTA with NaOH as the basic source, revealing the realization of shape-controlled synthesis of β-Ni(OH)2 nanostructures. Optical property of the NiO nanoparticles was conducted by means of UV–vis spectrum, exhibiting small blue shift compared with the bulk counterpart. The possible mechanisms for selective formation of β-Ni(OH)2 microspheres and nanoplates were in brief discussed. [Copyright &y& Elsevier]

Abstract: In this paper, we reported the successful preparation of fluorine-doped tin oxide (FTO) thin films on large-area glass substrates (1245mm×635mm×3mm) by self-designed offline atmospheric pressure chemical vapor deposition (APCVD) process. The FTO thin films were achieved through a combinatorial chemistry approach using tin tetrachloride, water and oxygen as precursors and Freon (F-152, C2H4F2) as dopant. The deposited films were characterized for crystallinity, morphology (roughness) and sheet resistance to aid optimization of materials suitable for solar cells. We got the FTO thin films with sheet resistance 8–11Ω/□ and direct transmittance more than 83%. X-ray diffraction (XRD) characterization suggested that the as-prepared FTO films were composed of multicrystal, with the average crystal size 200–300nm and good crystallinity. Further more, the field emission scanning electron microscope (FESEM) images showed that the films were produced with good surface morphology (haze). Selected samples were used for manufacturing tandem amorphous silicon (a-Si:H) thin film solar cells and modules by plasma enhanced chemical vapor deposition (PECVD). Compared with commercially available FTO thin films coated by online chemical vapor deposition, our FTO coatings show excellent performance resulting in a high quantum efficiency yield for a-Si:H solar cells and ideal open voltage and short circuit current for a-Si:H solar modules. [Copyright &y& Elsevier]

Abstract: Highly ordered nanorods array of B phase vanadium dioxide was firstly synthesized with n-butanol as the reducing agent via a simple hydrothermal method without using template. The samples have been characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and field emission scanning electron microscopy (FE-SEM). The size of VO2 (B) nanorods has the dimension of 50–100nm in diameter and about 1–5μm in length. The samples were measured as electrode materials by charge–discharge technique and the VO2 (B) nanorods array demonstrated a high specific capacity of 520mAh/g at 0.2C. The influence of reaction temperature on fabricating nanorods array has been studied. The possible growth mechanisms of formation of nanorods and assembly of array were discussed. [Copyright &y& Elsevier]

Abstract: In this study, polycrystalline linneite (Co3S4) nanotubes constructed with nanoparticles have been firstly fabricated using 1D Co(CO3)0.35Cl0.20(OH)1.10 nanowires as the sacrificial templates under hydrothermal conditions. The samples are characterized by means of XRD and TEM. The formation mechanism of the Co3S4 nanotubes can be explained by the nanoscale Kirkendall effect, which results from the difference in diffusion rates between cobalt source and hydrogen sulfide. This simple synthetic route is expected to prepare other nanomaterials with the tubular structures. [Copyright &y& Elsevier]

Abstract: A hydrothermal co-reduction method has been developed to fabricate ferroselite (FeSe2) nanorods and frohbergite (FeTe2) nanocrystallites using N2H4·H2O as the reductant. The experimental results indicate that the concentration of N2H4·H2O and the proportion of the starting materials play important roles in obtaining pure FeSe2 and FeTe2 nanocrystallites. Meanwhile, the magnetic properties of the as-obtained FeSe2 and FeTe2 nanocrystallites are measured at room temperature. [Copyright &y& Elsevier]

Abstract: A facile solution-phase approach has been developed to selectively fabricate metastable molybdenum dioxide, MoO2, nanocrystallites in an ethylene glycol/water mixed solvent. The experimental results reveal that the volume ratio of ethylene glycol has an important influence on the phase of the products based on XRD characterization. To our knowledge, it is the first time that metastable MoO2 nanocrystallites were synthesized through a solution route under mild conditions. [Copyright &y& Elsevier]

Abstract: Orchid-like Cr-doped MnO2 nanostructures have been synthesized via a hydrothermal method, using KClO3 as the oxidant. The as-obtained samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectra (XPS), transmission electron microscopy (TEM) and field emission scanning electron microscopy (FE-SEM). Results show that the morphologies of orchid-like MnO2 are made up of nanorods. The influences of chromium in the solution on the morphology of the products are discussed. The electrochemical characterization was carried out by cyclic voltammetry, which indicated that the products were excellent electrode material for super-capacitor. [Copyright &y& Elsevier]

Abstract: In this study, we present a facile biomolecule-assisted solution-phase approach to fabricating 1D hematite (- Fe2O3) nanowires on a large scale, in which glycine was used as the capping agent in solution. A series of time-dependent experiments reveal that the resulting - Fe2O3 nanowires grow preferentially along the (001) direction possessing the oriented attachment mechanism with the help of glycine. This facile synthetic strategy might be extended to prepare other inorganic nanomaterials with anisotropic morphology. [Copyright &y& Elsevier]

Abstract: An acidification-hydrothermal method was developed to synthesize α-MnO2 nanowires, which was subsequently treated with ethanol, resulting in γ-Mn2O3 nanowire bundles on a large scale. The electrochemical characterization was carried out by cyclic voltammetry, which indicated that the α-MnO2 nanowires in 0.5molL−1 Na2SO4 aqueous electrolyte was of an excellent electrode material for supercapacitor at the scan rate of 10mVS−1 in the range of 0.0–0.85V. [Copyright &y& Elsevier]

Herein, the precise fabrication of Sb 2 S 3 and low Se content Sb 2 Se y S 3- y indoor photovoltaics is reported, and a measurement protocol for photovoltaic performance is suggested and applied. Insertion of the SnO 2 buried layer decreases the thickness and parasitic absorption of the CdS layer. The introduction of minor Se into Sb 2 S 3 and the use of spiro -OMeTAD:TMT-TTF improve the charge transport of indoor photovoltaics. Using a white light-emitting diode (LED) under illuminance of 1000, 500, and 200 lx with color temperatures of 3347 and 6103 K, indoor photovoltaics with fluorine doped tin oxide (FTO)/SnO 2 (17 nm)/CdS (20 nm)/Sb 2 S 3 / spiro -OMeTAD:TMT-TTF/Au exhibit power conversion efficiency (PCE) values of 17.59, 16.66, 16.44, 16.56, 15.50, and 14.07%, respectively. Indoor photovoltaics with FTO/SnO 2 (17 nm)/CdS (20 nm)/Sb 2 Se y S 3- y (Sb/S/Se = 1:1.42:0.06)/ spiro -OMeTAD:TMT-TTF/Au achieve PCE values of 18.53, 17.62, 17.07, 17.30, 16.24, and 15.38%, respectively. The PCE values of 17.59, 16.66, and 16.44% are the highest values reported for Sb 2 S 3 indoor photovoltaics, and the other PCEs are all reported for the first time. Considering the trillion-dollar-sized market from the Internet of Things (IoT), this work can further bring an unprecedented thrust to the development of self-powered IoT devices by harvesting energy from indoor photovoltaics, thereby realizing the recycling of photon energy and reducing the use of batteries and the emission of CO 2 .

The solution-phase ligand-exchange strategy offers a simple pathway to prepare PbS quantum dots (QDs) and their corresponding solar cells. However, the production of high-quality PbS QDs with reduced surface trap state density for efficient PbS QD solar cells (QDSCs) still faces challenges. As the hydroxyl group (-OH) has been demonstrated to be the primary source of the surface trap states on PbS QDs in the general oleic acid method, here, we present an effective and facile strategy for reducing the surface -OH content of PbS QDs by using acetonitrile (ACN) as precipitant to wash the surface of QDs, which significantly decreases the trap state density and enables the preparation of superior PbS QDs. The resulting solar cell with an ITO/SnO 2 /n-PbS/p-PbS/Au structure obtained an improved photoelectric conversion efficiency (PCE) from 8.53 to 10.49% with an enhanced air storage stability, realizing a high PCE for SnO 2 -based PbS QDSCs., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

CH3NH3PbI3-xBrx thin films with different Br contents were successfully prepared on TiO2 nanorod array using 1.7 M PbI2 · DMSO complex solution and 0.465 M CH3NH3x(x = Br, I) precursors with different CH3NH3Br contents (molar ratios) by sequential deposition method. The influence of CH3NH3Br contents on the chemical composition, crystallinity, optical absorption and surface morphology of the CH3NH3PbI3-xBrx thin films was systematically investigated, and the photovoltaic performance of the corresponding TiO2 nanorod array perovskite solar cells was evaluated. The results revealed that the CH3NH3PbI3-xBrx solar cells using CH3NH3x precursors with 5% CH3NH3Br exhibited the best photoelectric conversion efficiency (PCE) of 16.47%, along with an open-circuit voltage (Voc) of 1.02 V, short-circuit photocurrent density (Jsc) of 20.99 mA · cm-2 and fill factor (FF) of 0.77, and the average PCE of 16.06 ± 0.52%, along with Voc of 1.02 ± 0.01 V, Jsc of 20.41 ± 0.58 mA · cm-2 and FF of 0.77 ± 0.01 under illumination of simulated AM 1.5 sunlight (100 mA cm-2).

In this paper, a two-layer structured PbI2 thin film was constructed by the spin-coating procedure using a 0.80 M PbI2 solution in DMF and subsequent close-spaced vacuum thermal evaporation using PbI2 powder as a source. The bottom PbI2 thin film was compact with a sheet-like appearance, parallel to the FTO substrate, and can be easily converted to a compact perovskite thin film to suppress the charge recombination of the electrons of the TiO2 conduction band and the holes of the spiro-OMeTAD valence band. The top PbI2 thin film was porous with nano-sheet arrays, perpendicular to the FTO substrate, and can be easily converted to a porous perovskite thin film to improve the hole migration from the perovskite to spiro-OMeTAD and the charge separation at the perovskite/spiro-OMeTAD interface. The planar perovskite solar cells based on the two-layer structured PbI2 thin film exhibited a photoelectric conversion efficiency of 11.64%, along with an open-circuit voltage of 0.90 V, a short-circuit photocurrent density of 19.29 mA cm(-2) and a fill factor of 0.67.