Search

In this research literature, a tungsten disulfide/iron cobaltite (WS

Transition metal molybdates/carbonates and hybrid nanomaterials have attracted great attention in energy storage applications because of their enriched redox activity, good electronic conductivity, and stable crystallinity. We synthesize a multicomponent MnMoO4/MnCO3 hybrid by a one-step hydrothermal method with urea as the reaction fuel. By controlling only the urea concentration in the initial precursor solution, the MnMoO4/MnCO3 molecular ratio is controlled effectively, which is found to have a profound effect on the electrochemical properties of the hybrid electrodes. The electrochemical measurements show that the specific capacitance of MnMoO4/MnCO3 hybrid is 1311 F/g, the energy density of 116.8 Wh/kg, and power density of 383 W/kg at a current density of 1 A/g with 79% capacitance retention over 5000 cycles. The fabricated asymmetric supercapacitor device exhibits good energy storage performance, including the specific capacitance of 97 F/g along with the energy density of 26.5 Wh/kg and the power density of 657 W/kg at a current density of 1 A/g and good reversibility with capacitance retention of 85% after 2000 cycles and 70% over 5000 cycles. The increase in the energy density of 900% with a mere 60% decrement in the energy density indicates its potential superior applications in high-power devices.

Silicon wafers are significantly utilized in integrated circuits and memory devices for the fabrication of novel semiconductor devices. As a result, a substantial amount of silicon wastes are generated every year. But recycling process of pure silicon waste is expensive with an additional problem related to chemical waste generation. Thus, the possibility of inevitable silicon waste conversion into potential nanostructures is not only beneficial for the semiconductor industry but also resolves current e-waste pollution. Hence, we successfully achieved hexagonal silicon carbide (SiC) nanowires under a strategic combination of waste silicon wafers and graphite powder by robust high-energy ball milling and heat treatment approaches. Structural, morphological, chemical, and optical properties of SiC nanowires are systematically studied by XRD, SEM, TEM, XPS, and optical absorbance. This facile experimental technique recognized the value of SiC nanowire generation for exploring multifunctional photoelectrochemical (PEC) water splitting and antibacterial activity. Accordingly, SiC nanowires achieved a photocurrent density of about 0.21 mA cm−2 vs. Ag/AgCl, which demonstrates enhanced light absorption capacity under reduced charge carrier recombination. Moreover, SiC nanowires prevailed decrement in the charge carrier resistance (27.53 Ω) under light state compared to the dark state (26.76 Ω). Specifically, potentiodynamic studies revealed superior exchange current density (− 3.17 mA cm−2), Tafel slope (80.1 mV dec−1), and limiting diffusion current density (− 1.49 mA cm−2) under light state than the dark state. Also, these results are certainly applicable for superior antibacterial activity against E. coli and L. monocytogenes about 90% and 75% under visible light, respectively.

To meet the demand for the development of high energy storage devices, appropriate designs of advanced carbon nanostructures (CNs) with metal oxides are highly preferred. Herein, the surfaces of tw...

Perovskite solar cells with the structure of glass/florine-doped tin oxide (FTO)/electron transfer layer (ETL)/perovskite/hole transfer layer (HTL)/Ag were fabricated. The effects of blending solvents and thermal annealing on the surface morphology, structural, and optical properties of perovskite (CH3NH3PbI3) active layer were investigated. The active layer was optimized by adding 2-butanol (2-BTA) as an eco-friendly solvent into methyl ammonium iodide (MAI) solution used for spin coating on PbI2/(dimethylformamide (DMF)+dimethyl sulfoxide (DMSO)) film in the second step. The resulting morphology of CH3NH3PbI3 films was smooth and pinholes in the films were also reduced without change in the structure. The effects of thermal annealing on the surface morphology and structural properties of active layer were also studied. The fabricated device for the optimized condition showed the maximum power conversion efficiency (PCE) of ~8.6%.

Rational design of highly conductive and redox-active electrode materials composed of metal chalcogenides and carbon composites has attracted promising attention for the development of high-performance energy storage devices. Herein, cost-effective in situ design of carbon sheets with nickel sulfide shielded nickel (NiS–Ni@C) nanocomposite is prepared using biomass precursor with subsequent pyrolysis and sulfurization, respectively. Initially, highly conductive nickel nanospheres are permeated into carbon sheets (Ni@C) by the pyrolysis of carbon-rich wheat snacks and nickel salt. Following, core–shell-like hierarchical NiS flowers on Ni@C were derived in situ using various thiourea concentrations under hydrothermal treatment. Utilizing the hierarchical NiS–Ni@C as an electrode material, the highly conductive composite enables rapid diffusion of electrolyte ions into their interiors and accelerates redox chemistry during electrochemical measurements. Specifically, hierarchical NiS–Ni@C nanocomposite demonstrates dominant battery-type behavior with a maximum specific capacity of 430 C g−1 and excellent cycling stability of 92%. Moreover, a hybrid supercapacitor is assembled using hierarchical NiS–Ni@C as a positive electrode and wheat-snack derived porous carbon as a negative electrode, which exhibits superior energy and power densities with good cycling stability. The designed composite using biomass sources promotes the way for the development of highly active electrode materials for energy storage and electrocatalytic applications.

In the earth-abundant low-cost thin-film solar cells, selenide based chalcogenides such as CTSe (Cu2SnSe3) has been driven great attention in the photovoltaic applications. Therefore, potentially attractive, yet not well studied, copper-tin based chalcogenide material Cu2SnSe3 is reviewed comprehensively. This review article is mainly focused on the discussion about the physical properties of Cu2SnSe3, deposition techniques, and photovoltaic performance of the Cu2SnSe3 solar cells. In this review, the limiting factors in attaining the higher efficiencies and suggestions for efficiency improving methods of CTSe solar cells are discussed. This is the first comprehensive review, solely dedicated to Cu2SnSe3 thin films and corresponding photovoltaic applications, which can help the readers to attain the outline of Cu2SnSe3 thin films.

SnS is an earth-abundant, non-toxic, and low-cost absorber material for solar cell applications. In this work, the physical properties of SnS thin films and efficiency of SnS solar cells were investigated for different tin metal layer thicknesses of 300 nm (Sn-300), 500 nm (Sn-500), and 700 nm (Sn-700) deposited by DC sputtering followed by the sulfurization using effusion cell evaporation method. The XRD and Raman characterizations confirmed the formation of single-phase SnS compound with orthorhombic structure for the case of Sn-500. The sulfurized films of Sn-500 had remarkable and homogeneous morphology with the optical band gap energy of 1.35 eV. The fabricated device showed an efficiency of 0.74% with an open-circuit voltage of 267mV, short circuit current density of 8.47 mA/cm2, and fill factor of 54.16. By varying the different metal tin layer thicknesses, this is the first report with device efficiency for SnS solar cells grown via effusion cell evaporation technique.

Herein, this report uses Co

An “ink” solution based process, using spin-coating technique, followed by annealing in selenium environment with different temperature programs was utilized to prepare CIGSe thin films. Herein, the CuIn0.7Ga0.3Se2 nanocrystals were synthesized using ethanol — a “green” solvent. Three different solvents: 2-propanol, 2-methoxyethanol, and their 2: 1 mixture (v/v ratio), were investigated as a dispersion medium for the as-synthesized CIGSe nanocrystals to form a stable ink solution. The last one- a mixture of 2-propanol: 2-methoxyethanol=2: 1 (v/v), was found to be the most suitable. Furthermore, the influences of various annealing modes on the CIGSe grain size and density in the resulting film were also studied. The as-prepared CIGSe thin film was around 1 µm thick and possessed a tetragonal structure. A newly developed cheaper and “greener” non-vacuum process was applied successfully from the synthesis of nanocrystals to the formation of ink solution, and produced high quality thin films; this opens a new route to the cost-competitive commercialization of CIGSe thin film solar cells.

Tin monoselenide (SnSe) thin films with thickness in the range of 0.72–1.00 μm were prepared by the two-stage process (metallization by sputtering + selenization by rapid thermal annealing) using Sn target and selenium powder at different selenization temperatures in the range of 300–450 °C. The formation of single-phase orthorhombic(OR)-SnSe films at ≥ 400 °C was observed, whereas the secondary phase of SnSe2 in addition to OR-SnSe was formed when the films selenized at ≤ 350 °C. The single-phase OR-SnSe films exhibited Raman modes at 33 cm−1, 71 cm−1, 108 cm−1, 130 cm−1, and 151 cm−1. The crystallinity and grain size of the OR-SnSe films were improved with increasing of selenization temperature. The tin films selenized at 400 °C showed the composition ratio of Se/Sn = 0.99, the direct bandgap energy of 1.2 eV, and the p-type conductivity with electrical resistivity of 12.71 Ω cm, the mobility of 2.03 cm2 V−1 s−1, and carrier concentration of 2.42 × 1017 cm−3. The above opto-electronic properties of single-phase OR-SnSe films selenized at 400 °C indicated that these films could be used to attain good device efficiency of solar cells.

The rapid progress on the Cu–Sn–S (Cu2SnS3, Cu3SnS4, and Cu4SnS4) solar cells has opened a new avenue to generate the electrical energy at ultra-low-cost. Therefore, the progress in the deposition of Cu2SnS3, Cu3SnS4, and Cu4SnS4 thin films by various chemical and physical methods is reviewed comprehensively. This article briefly describes (i) the phase diagrams of Cu–Sn–S, (ii) the bulk properties of Cu2SnS3, Cu3SnS4, and Cu4SnS4, (iii) the effect of deposition conditions on the phase formation, (iv) the physical properties of Cu2SnS3, Cu3SnS4, and Cu4SnS4 thin films, and (v) the photovoltaic performance of Cu2SnS3, Cu3SnS4, and Cu4SnS4 solar cells.

In this study, the deposition of Cu2SnS3 (CTS) thin films was carried out at different sulfurization temperatures in the range of 350–550°C under high vacuum of 1 Pa using the sputtered Cu/Sn/Cu metal precursor layers in the sulfur vapor atmosphere. In order to reduce the Sn loss, a particular metal stack of Cu/Sn/Cu was used. Single phase monoclinic (M)-CTS thin film was obtained at 500 °C. The high intensity Raman modes at 292 cm−1 and 350 cm−1 further confirmed the formation of M-CTS. The M-CTS thin film sulfurized at 500 °C showed a composition of Cu/Sn = 1.89 and an optical band gap energy of 0.94 eV. Hall effect measurement of the film sulfurized at 500 °C with Cu/Sn ratio of 1.82 showed an electrical resistivity of 7.30 Ω-cm, carrier concentration of 6.29 × 1017 cm−3, and mobility of 1.36 cm2/Vs. Our results indicate that the copper-poor composition with a stacking order of Cu/Sn/Cu is favored in order to attain the single phase M-CTS.

Selenium (Se)-rich binary Cu-Se and In-Se nanoparticles (NPs) were synthesized by a modified heat-up method at low temperature (110 °C) using the gum exudates from a cherry blossom tree. Coating of CISe absorber layer was carried out using Se-rich binary Cu-Se and In-Se NPs ink without the use of any external binder. Our results indicated that the gum used in the synthesis played beneficial roles such as reducing and capping agent. In addition, the gum also served as a natural binder in the coating of CISe absorber layer. The CISe absorber layer was integrated into the solar cell, which showed a power conversion efficiency (PCE) of 0.37%. The possible reasons for low PCE of the present solar cells and the steps needed for further improvement of PCE were discussed. Although the obtained PCE is low, the present strategy opens a new path for the fabrication of eco-friendly CISe NPs solar cell by a relatively chief non-vacuum method.

Vanadium nitride and porous carbon are emerging as new class of electrodes and are extensively being explored as high-performance supercapacitor (SC) materials for their interesting properties. In this study, vanadium nitride@porous carbon (VN@C) nanostructured hybrid material for SCs is synthesized utilizing in-situ, one-pot chemical synthesis technique. The VN@C hybrid nanostructure has achieved very high capacitance by utilizing the combinations of electric double layer capacitive (EDLC) properties of porous carbon and pseudocapacitive characteristics of VN nanoparticles (VN NPs) and delivered maximum specific capacitance of 1850 C g−1 @10 A g−1 current density, with an excellent rate capability of 98% over 2000 cycles. Exploring the excellent electrochemical characteristics of VN@C, an asymmetric supercapacitor (ASC) cell is constructed with activated carbon (AC) as negative and VN@C as positive electrode. Remarkably, the as-constructed VN@C//AC ASC device achieves an excellent capacitance of 102 F g−1 at 1 A g−1 with the energy and power densities of 17–30 Wh kg−1 and 701–5608 W kg−1, respectively, over the current density range of 1–8 A g−1. Our facile preparation of highly porous carbon nanobelt-vanadium nitride composite along with high-energy storage properties pave the way for the development of various carbon–metal nitride hybrid nanostructures for promising energy storage applications.

Ternary compound for engineering nanoarchitecture of MnCo2S4 has been hierarchically well maintained and attractive surface area was regarded as a potentially efficient technique to grow novel electroactive materials. In this regard, crafting Nano flower-built MnCo2S4 nanoarchitecture with Ni foam network favors short path roots and interconnected for excellent charging transfer and ion transmission, which allows the energetic Faradaic redox procedures by the improves active surface. According to the structural and compositional features, the as-developed MnCo2S4 nanoflower nanoarchitecture exhibits superior electrochemical capacity activities. Impressively, the MnCo2S4 nanoflowers achieve an excellent specific capacitance of 779 F g−1 at a current density of 1 A g−1, which causes unique features of structural construction. When tested long-term cycling stability performance, the as-constructed MnCo2S4 nanoflowers achieves excellent capacitance retention 96.5% over 3000 cycling stability performance at a current density of 2 A g−1 with superior conductivity. Considered the above points, the simplistic approach yet unique construction of this MnCo2S4 holds substantial potential energy conversion and high-performance energy storage.

Over the last two decades, magnetic hyperthermia (MH) has become a significant capable additional method to well-recognized cancer treatments such as chemotherapy and radiotherapy. The Mg1−xNixFe2O4 (x = 0.1, 0.2, 0.3, 0.4 and 0.5) spinel ferrite nanoparticles (SFNPs) were successfully synthesized and assessed them as agents for MH affect. The synthesized NPs were well characterized for structure, morphology, and particle size, and weight loss using X-ray diffractometer (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectrophotometer (FT-IR), and thermogravimetric analysis (TGA). Prepared powder samples saturation mass magnetization (Ms) values were enhanced with the enhancing of the Ni2+ -concentration. The Ms values were found to be 40.72–48.18 emu g−1. The synthesized SFNPs as MH agents display well specific heat generation rate (SGHR) values 97–328 W g−1 at a constant frequency of 316 kHz, hence the present synthesized SFNPs could be useful for MH applications and can be used as a significant heating cause for thermal therapy MH treatment of cancer. The synthesized samples were exhibits good Ms, best morphology, monodispersed performance, significant Ms and best SHGR values. All these types of characteristics are vital, for their use in MH treatment of cancer application. The photocatalytic degradation efficiency (DE%) was examined by degrading methylene blue (MB) under visible light radiation in the multi-lamp photoreactor. Our results designate that, Ni2+-substituted MgFe2O4 SFNPs can be best employed for effective wastewater purification. Nearly monosized Ni2+- doped MgFe2O4 NPs exhibited better photocatalytic activity of MB under visible light radiation. These types of catalysts could be useful in wastewater treatment applications. The synthesized biocompatible magnetic semiconductor nanoparticles can be utilized as photocatalysts and could also be recycled and separated by applying an external magnetic field. The developments of monosize NPs with significant Ms are required for advanced biomedical as well as electronic applications. Cytotoxicity studies conducted in MCF-7, MDA-MB-231 breast cancer cells, and normal keratinocyte cells showed that the synthesized NPs are biocompatible but possessed a very toxic effect on MCF-7 and MDA-MB-231 cell lines may be owing to the generation of reactive oxygen species and/or ferroptosis.

Single-phase monoclinic Cu2SnS3 (M-CTS) thin films have a good tendency to obtain high conversion efficiency in photovoltaic devices. In this study, single-phase monoclinic Cu2SnS3 (M-CTS) thin films are prepared by a combination of sputtering and sulfurization processes. The M-CTS device shows a power conversion efficiency of 0.64% with an open-circuit voltage of 0.184 V, a short circuit current of 12.63 mA/cm2, and fill factor of 27.36. The required single-phase structure of M-CTS is confirmed by the X-ray diffraction and Raman spectroscopy. Quantitative analysis by a Rietveld refinement of the XRD patterns of CTS films reveal a monoclinic crystal structure. The M-CTS thin-film shows a compact morphology, direct optical bandgap of 0.95 eV, a thickness of ~1 μm, and electrical properties, including resistivity of 1.50 Ω-cm, hole mobility of 5.02 cm2/V, and carrier concentration of 8.30 × 1017 cm−3 with p-type conductivity. Based on these advantages, further studies are expected to drastically enhance the efficiency of M-CTS solar devices.

The undoped and indium doped SnSe (In-SnSe) thin films were successfully prepared by the two-stage process (sputtering and rapid thermal annealing process). The physical properties of the prepared thin films were investigated. Crystallographic patterns of the undoped and doped SnSe thin films showed the single-phase orthorhombic-SnSe. The diffraction peaks slightly shifted towards the higher diffraction angles as well as Raman peaks also shifted towards higher Raman shift by doping of indium. Morphology of the In-SnSe films changed significantly by changing the indium percentage. The optical bandgap of SnSe and In-SnSe films was varied in between 1.06 eV and 1.50 eV, and the electrical properties of In-SnSe films were significantly changed with dopant concentration. The obtained physical properties of In-SnSe thin films are suitable for solar cell device fabrication.

Cu2SnSe3 thin films were prepared by the two-stage process (metal layers deposited by direct current-sputtering + selenization of metal layers by rapid thermal annealing). The effect of selenization temperature (350 °C-550 °C) on the physical properties of Cu2SnSe3 was investigated thoroughly. The formation of single-phase Cu2SnSe3 was confirmed by the X-ray diffraction patterns of the selenized films at 550 °C. The Raman modes at 181 cm−1 and 231 cm−1 confirmed the formation of single-phase Cu2SnSe3 at 550 °C and the presence of secondary phase identification was also investigated. The compositional and morphological analysis was investigated using energy-dispersive X-ray spectrometer and field emission scanning electron microscopy measurements, respectively. The optical properties of selenized films were measured by the ultraviolet-visible spectroscopy and the calculated results showed the bandgap values in the range 0.9-1.44 eV. The Hall Effect measurement showed that the values of carrier concentration were decreased and the resistivity was increased with increasing of selenization temperature.