Herein, we synthesized a Cu2O and Co3O4 incorporation with MoS2 to produce MoS2/Co3O4/Cu2O nanocomposites by facile sonication assisted hydrothermal methods. The phase structure and elemental composition of MoS2/Co3O4/Cu2O nanocomposites were investigated using X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) techniques. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) morphology studies confirm that MoS2/Co3O4 nanostructure self-assembles in a mixed nanosheet configuration after the introduction of Cu2O. The synthesized samples were used as new types of Pt-free counter electrodes (CE) for DSSCs. Among all, the DSSCs based on the MoS2/Co3O4/Cu2O CE yields a maximum power conversion efficiency of 3.68 % (Jsc = 8.2 mA cm?2, Voc = 0.71 mV and FF = 0.629 %) under the standard AM 1.5 G illumination, which is 2.5 times higher than that of pure MoS2. To assess the photocatalytic activity, prepared samples were used to suppress methylene blue (MB) and rhodamine B (RhB) dye under UV–visible light irradiation. The MoS2/Co3O4/Cu2O nanocomposites had the highest photocatalytic degradation efficiency of all the samples. It increased degradation efficiency from 43 % to 91 % for MB dye after 100 minutes, and from 47 % to 92 % for RhB dye after 90 minutes. Scavengers test analysis proved that the superoxide radical (•O2?) play a major role in the MoS2/Co3O4/Cu2O photocatalytic system. After four consecutive photocatalytic cycles, the crystal structure and surface morphology of the MoS2/Co3O4/Cu2O nanocomposites used in the 4th cycle were more stable, and this was confirmed by SEM, EDAX and XRD studies. The broader significance of these findings provides a straightforward approach for synthesizing a low-cost and high-efficiency MoS2/Co3O4/Cu2O nanocomposite for CE in DSSC photovoltaic cells and facilitates organic pollutant removal through photocatalytic applications. © 2024 Elsevier B.V.

Two tungsten-based oxides, Li2WO4 and h-WO3, were investigated as anode materials for lithium-ion batteries in half-cell configuration (vs. Li) within the voltage window of 3.0–0.05 V. The initial lithiation process in both materials involves Li intercalation into the lattice, followed by a conversion reaction. The Li2WO4 anode exhibited outstanding electrochemical performance, delivering a high reversible capacity of 547 mAh g?1 at 0.1C and 355 mAh g?1 at 1C after 70 cycles. Furthermore, it demonstrated fast charging capability and exceptional cycling stability, maintaining a discharge capacity of 280 mAh g?1 at 5C even after 1500 cycles. In comparison, the h-WO3 anode displayed significantly lower performance under similar conditions. These results highlight that the presence of pre-existing lithium ions in the host lattice of Li2WO4 facilitates efficient lithiation and delithiation, contributing to its superior capacity and extended cycle life. This study underscores the potential of Li2WO4 as a promising anode material for next-generation lithium-ion batteries

NCM-622 cathodes have been promising cathodes for lithium-ion batteries due to their high reversible specific capacity and low cost. However, the NCM-622 cathode suffers from structural instability, especially at high voltage. Moreover, at elevated voltages and temperatures the cathode suffers from surface side reactions and particle cracks due to the presence of grain boundaries. The in situ doping of Mg2+ is achieved by doping Mg ions during the synthesis procedure using a CSTR and the LiBO2/B2O3 surface coating is achieved by a simple wet-chemistry method; this dual-modification not only protects the surface of the cathode but the Mg2+ ions in the structure also enhance the cycling stability even at high voltage (4.5 V) and temperature (55 °C). As a result, animproved electrochemical behaviour was observed and the cathode could retain 82.5% of its initial capacity after 100 cycles at 4.5 V. Furthermore, the presence of the hybrid coating on the surface protects the cathode from HF attack and reduces the voltage polarisation during high temperature and voltage cycling. Such a dual-modification strategy can be commercially viable and useful for modification of high-energy-density NCM-622 cathodes.

Inducing post-transition metals in an oxide semiconductor system has a high potential for use in storage for neuromorphic computing. It is challenging to find a material that can be switched stably between multiple resistance states. This research explores the memristive properties of Sn (post-transition metal)-doped ZnO (SZO) thin films, emphasizing their application in memristor devices. The (magnetron sputtered) synthesized SZO thin films in the form of Ag/SZO/Au/Ti/SiO? device demonstrated a clear bipolar resistive switching (BRS) behavior with VSET and VRESET of 1.0 V and ?0.75 V, respectively. The memristor could change between a high resistance state and a low resistance state with a high RON/OFF rate of 104, mimicking synaptic behaviors such as potentiation and depression. This switching is attributed to the formation and dissolution of Ag filaments within the SZO layer, influenced by the migration of Ag? ions and the presence of oxygen vacancies. These vacancies facilitate the formation of conductive filaments under positive bias and their dissolution under negative bias. The endurance and retention tests showed stable switching characteristics, with the memristor maintaining distinct HRS and LRS over 100 cycles and retaining these states for over 5K seconds without significant degradation. Finally, the nonlinearity values for potentiation and depression were ?p?1.6 and ?d ? -0.14, suggesting that the memristor may be more responsive to increasing synaptic weights in biological systems. The linearity response at a very small pulse width showed the device is more applicable for neuromorphic applications. The observed memristor combined with stable endurance and retention performance, suggests that this memristor structure could play a crucial role in the development of artificial synapses and memory technologies. © 2024 Elsevier Ltd

Green Hydrogen emerges as a promising energy solution in the quest for achieving Net Zero goals. The application of particulate semiconductors in photocatalytic water splitting introduces a potentially scalable and economically viable technology for converting solar energy into hydrogen. Overcoming the challenge of efficiently transferring photoelectrons and photoholes for both reduction and oxidation on the same catalyst is a significant hurdle in photocatalysis. In this context, we introduce highly efficient crystalline elemental boron nanostructures as photocatalysts, employing a straightforward and scalable synthesis method yield green hydrogen production without the need for additional co-catalysts or sacrificial agents. The resulting photocatalyst demonstrates stability and high activity in H 2 production, achieving over 1 % solar-to-hydrogen energy conversion efficiency (>15,000 ?mol. g ?1.h ?1 ) during continuous 12-h illumination. This efficiency is credited to broad optical absorption and the crystalline nature of boron nanostructures, paving the way for potential scale-up of reactors using crystalline boron photocatalysts.

We developed the MoS 2 -MgOH 2 -BiVO 4 hybrid via the hydrothermal technique for counter electrode (CE) of dye-sensitized solar cells (DSSC). The prepared samples were confirmed by XRD and FTIR analysis. The optical studies were done by ultraviolet–visible spectra, which confirmed the narrowing bandgap of the MoS 2 -Mg(OH) 2 -BiVO 4 hybrid. The morphological structure of MoS 2 nanorods was turned into MoS 2 -Mg(OH) 2 -BiVO 4 ternary hybrid hierarchical nanosheets that coexisted with particles. The MoS 2 -MgOH 2 -BiVO 4 counter electrode and commercial TiO 2 photoanode were utilized for constructing the DSSC solar cell. According to the photovoltaic responses of the DSSC, the ternary square-like MoS 2 -MgOH 2 -BiVO 4 hierarchical nanosheets were 1.48 times more effective than pure MoS 2. The charge transfer mechanism of ternary hybrid photovoltaic was investigated and discussed.

Emerging novel 2D materials with unique electrochemical properties generate massive interest among researchers to fabricate the supercapacitors with high energy density without fading actual power density. In present work, a novel 2D Bismuthene-Molybdenum disulfide composite (Biene-MoS 2 NC) was synthesized which serves as an effective active material for the fabrication of electrodes for supercapacitors with superior electrochemical characteristics. The synthesized Biene-MoS 2 NC electrode provides the improved specific capacity of 195.9 mAh/g at the sweep rate of 10 mV/s together with the total stored capacity, outer surface adsorption capacity, and intercalation capacity of 285, 10.8, and 274.2 mAh/g respectively and their percentage of capacitance and diffusion of 36.3 % and 63.7 % respectively. The pouch type supercapacitor cell was fabricated using Biene-MoS 2 NC as positive electrode (cathode) and activated carbon (AC) as negative electrode (anode) which demonstrated high areal capacitance of 38.2 mF/cm 2 at the current density of 0.5 mA/cm 2 and also it delivered the enhanced areal energy and power densities of 11.94 ?Wh/cm 2 and 1 mW/cm 2 respectively.

Biomass-derived carbon showed much promise as it eliminates fossil fuel dependency and has several other advantages, such as being renewable, abundant, and environmentally friendly. In the present study, activated carbon is derived from foetida biomass using a single-step synthesis method. Nitrogen-doping studies were carried out to improve the electronic conductivity and found that the 1:0.5 weight ratio of carbon to nitrogen source is a critical composition which exhibited improved electronic conductivity without losing substantial surface area and porosity. The critical composition showed outstanding electrochemical performance versus Li-metal, with a reversible discharge capacity of 423 mAh/g at 0.1A/g current density. Also, it showed good cycling stability, 310 mAh/g after 100 cycles at 0.1A/g current density. The nitrogen-doped activated carbon material has the potential to be used as anode material in rechargeable Li-ion batteries.

Ni-rich cathodes are very attractive in terms of high-energy density cathodes. However, it still suffers from various disadvantages, making commercialization more difficult. A dual-modifying cathode is a simple and efficient strategy that can have a synergistic effect of surface coating on the outside, and doping can have internal structure stabilization. CSTR-level doping of Mg can significantly extend the battery’s cycle life due to its pillar effect, and LiNbO is a prominent coating material with high ionic conductivity. The dual-modified cathode in this study has shown excellent electrochemical performance in terms of cyclic stability and rate performance, even at 4.5 V vs. Li. The modified cathode showed 85.4% capacity retention at 4.3 V and 87.11% at 4.5 V, whereas the bare showed only 78.9% and 68.2%, respectively. The LiNbO-coating protects the material from the surface side reactions from the electrolytes at high voltage operations, and the “pillar effect” due to Mg doping stabilizes the structure for longer cycles and higher C-rates, making this dually modified cathode a prominent cathode material for lithium-ion batteries. Graphical abstract: (Figure presented.)

Biomass-derived activated carbon materials have been attracted as low-cost and sustainable electrode materials for energy storage applications. In this work, we synthesised activated carbon from black gram whole skin for the first time, and the used source is a cost-effective carbon precursor. Nitrogen and phosphorous doping in activated carbon improved electronic conductivity, surface area and porosity. In supercapacitor application, the nitrogen and phosphorous doped activated carbon sample showed a high specific capacitance of 425 F g ?1 at 0.5 A g ?1 and cycling stability of about 92.5 % capacitance retention even after 5000 cycles in a three-electrode system. The observed stable specific capacitance in a three-electrode system encouraged us to make a two-electrode symmetric device, showing a specific capacitance of 100 F g ?1 at 0.5 A g ?1 with a higher energy density of 20 Wh kg ?1. In addition, the lithium storage capability of doped carbon showed good capacity of 750 mAh g ?1 at 0.1 A g ?1 with a reversible capacity of 687 mAh g ?1 after 100 cycles. The hetero-atom doped activated carbon derived from black gram skin showed outstanding electrochemical performance towards supercapacitor and lithium battery application, indicating a potential alternative to fossil fuel-derived carbon.

The increasing global demand for energy solutions has created the necessity for innovative nanocomposite materials for efficient energy storage applications. This urgency is driving significant advancements in energy storage technologies, raising hope for the future of energy sectors. Supercapacitors (SCs), high-performance electrochemical storage devices, have earned considerable attention to address these challenges. In this article, we have demonstrated a cost-effective, easily obtainable trimetallic spinel/defect-spinel oxide ZnMnO/CuMnO (ZMO/CMO) nanocomposite through a facile one-step solvothermal synthesis process. This nanocomposite demonstrated exceptional charge storage capabilities. The charge storage mechanism was established by using Dunn’s method, which reveals the diffusive nature of the electrode material. The ZMO/CMO nanocomposite exhibits an impressive specific capacitance of 468.1 F/g at 0.5 A/g, with 84% capacity retention even after 20000 cycles, which was attributed to the oxygen vacancies within the defect spinel structure. Moreover, we fabricated an asymmetric device utilizing ZMO/CMO as the cathode and activated carbon (AC) as the anode. This device attained an energy density of 48.1Wh/kg and a power density of 700 W/kg with excellent cycling stability, as mentioned before. Furthermore, our study featured its ability to power a standard LED light.

In our ecologically concerned world, the growing demand for energy to support human needs presents an increasing issue. The current primary energy source's heavy reliance on fossil fuels not only depletes limited resources but also greatly increases environmental pollution. The solution to this conundrum is a radical move in the direction of sustainable alternatives, of which solar energy is a prime contender because it produces no pollution. It is essential to switch completely to solar energy from conventional energy sources in order to ensure a cleaner and greener future. However, the investigation and implementation of novel systems that smoothly combine solar energy harvesting and storage into a single apparatus. Remarkably, the integration of solar energy conversion and storage systems is still undergoing significant advancements, as the scientific community has recently embarked on exploring this subject. This study investigates a pressing need in modern times: the development of a singular gadget known as “photo-supercapacitors”. The performance and efficiency of the system are thoroughly examined by assessing the crucial factors. The paper provides a thorough overview of the progress made in enhancing the flexibility and efficiency of photo-supercapacitors, offering valuable insights into the promising future of energy systems and technology. © 2024 Elsevier Ltd

The oxide-based narrow band red emitting phosphor is critical and assumes a fundamental part to upgrade the overall efficiency of the white LED. In this regard, a series of Eu3+-activated Na2La4(WO4)7 (NLW) red emitting phosphors were synthesized employing a solid state approach, and we examined their optical properties in detail. All of the compositions crystallize in tetragonal structure with a I41/a space group. Sharp red emission was exhibited by all the NLW:Eu3+ phosphors ~616 nm owing to the ED transition (5D0 ? 7F2), under the excitation of 394 nm and observed concentration quenching when x = 0.8. In addition, color purity and IQE of Na2La3.2(WO4)7:0.8Eu3+ phosphor is found to be 96.79% and 83.76%, respectively. A temperaturedependent PL study reveals the thermal stability of the phosphor as 69.75% at 423 K. Red and white LEDs were fabricated utilizing the synthesized phosphor to understand their practical applicability. EL spectra of the red LED displayed intense red emission, whereas white LED exhibited warm white light with high CRI (80) and low CCT (5730K) values. These Eu3+-doped red phosphors can also be used for latent fingerprint application. Moreover, a series of Sm3+ and simultaneous activation of both Sm3+ and Eu3+ in NLW phosphors were synthesized, and investigated their optical properties. By using the Sm3+-codoped Eu3+-activated phosphor, a red/deep red LED is fabricated for the plant growth purpose. These outcomes suggested that the synthesized phosphors could be promising phosphors for the WLED, security, and plant growth applications.

Dual-modified Zr-doped and ZrO-coated NCM-622 with excellent electrochemical properties was synthesized by simple wet-chemical coating. X-ray diffraction analysis revealed the unit cell expansion along the c-direction in the Zr-modified sample, which was substantial in improving the lithium-ion kinetics. The surface coating of ZrO was visible in TEM images protecting the cathode from surface-side reactions. The electrochemical performance of the Zr-modified sample was superior to that of the other modified and uncoated samples; it showed higher cyclic stability even after 100 cycles at a 1C rate and offers 86.3% capacity retention, whereas the unmodified sample yielded only 21.7% of its initial capacity. Zr doping acts as a pillar, stabilizing the structure to provide better Li diffusion and increased cyclability and rate capability. Further analysis showed that the Zr-modification has shown superior electrochemical performance and cyclic stability even at elevated temperatures of 55 °C. The ZrO coating on the surface can act as an HF scavenger during cycling at high temperatures. The superior cycling stability and rate capability can be attributed to the synergetic effect of simultaneous doping and coating of zirconia on the NCM-622. Graphical abstract: [Figure : see fulltext.].

Advanced two dimensional nanostructures with distinctive physicochemical properties, excellent surface chemistry, and adjustable interlayer band-gap enhances the electrochemical activity in the field of supercapacitors. This work focuses on the formation of the hybrid nanocomposite of Bismuthene-Multiwall carbon nanotube nanocomposite (Biene-MWCNT NC) to enhance the electrochemical activity. Cyclic Voltammetry (CV) analysis of Biene-MWCNT NC reveals the enhanced specific capacity of 323.65 C/g at the scan rate of 10 mV/s. In addition, the Trasatti method shows the charge accumulation mechanism which delivering the total, inner, and outer capacity of 662.3, 601.02, and 61.23 C/g respectively together with the capacity and diffusion contribution percentages of 90.76 % and 9.24 % correspondingly. Furthermore, Biene-MWCNT//MWCNT hybrid supercapacitor (HSC) demonstrates the elevated specific capacity of 113.85 C/g at the constant current density of 0.5 A/g and the outstanding energy density of about 35.5 Wh/kg corresponds to high power density of 11250 W/kg.

Herein, we report the Li-ion conducting composite material, Li 0.57 La 0.29 TiO 3 (LLTO), coated on a microporous polyethylene separator to use in rechargeable Lithium-metal batteries. Since the LLTO contains structural Li-ions and the three-dimensional conducting channels within, it not only improved the ionic conductivity of coated separator but also improved the surface electrolyte wettability and suppressed the dendrite formation. As a result, the Lithium-metal battery cycling stability and safety features are increased. Consequently, the ceramic composite separator enabled a specific capacity of 105.6 mAhg ?1 for Li/LiMn 2 O 4 coin cell, and 80 % capacity retention is observed even after 500 cycles at 1C, indicating its promising practical potential application. This work provides a feasible and efficient modification strategy of separators for improving the cycling performance and safety of Lithium-metal batteries. In addition, the ceramic composite-coated separator could instill confidence in using Lithium metal as the attractive anode for high-capacity Li-air and Li?sulfur batteries with enhanced thermal and cyclic stability.

Ever growth in the energy demand has catapulted us to explore various energies. Henceforth, to meet these ends, among the different cathode active materials, nickel (Ni) rich polycrystalline (PC) cathode materials have been known to serve the purpose aptly. Yet, these PC Ni-rich cathode materials have yielded inferior performances with an increase in voltage and temperature. The absence of grain boundaries in the intrinsic structure, high mechanical strength, high thermal stability, and controllable crystal faucet have made SC cathodes a better prospect. Yet, there are challenges to overcome in the SC cathodes, like larger crystals hindering the Li transport, which leads to disappointing electrochemical performance. Through this perspective article, we wish to elucidate the crucial factors that facilitate the growth of SC-NCM cathode, viable dopants, and coating materials that could enhance the performance, future scope, and scalability of SC-NCM at the Industrial level.

The recent surge of research in the development of sodium-ion batteries (SIBs) as an alternative to the lithium-ion batteries (LIBs) has shown that the SIBs can reduce the load of the LIBs in certain areas. However, the development of SIBs in the commercial arenas is yet to be tapped. This perspective delineates the importance of Ni-rich cathodes and various strategies to ameliorate the performance of the Ni-rich cathodes in the SIBs. Also, discussed various synthesis routes for the industrial-scale synthesis of Ni-rich materials and tried to elucidate the importance of SC cathodes and the necessity to develop those in SIBs.

Pure and Mn-doped ZrO 2 nanocrystals (Zr 1-x Mn x O 2 ) with varying Mn concentrations (x ?= ?0.02, 0.04, 0.06, and 0.08) have been synthesized using sol-gel method. The effect of Mn doping concentration on structural, optical and magnetic properties has been investigated. X-ray diffraction data and SAED analysis revealed that all Zr 1-x Mn x O 2 nanocrystals have a tetragonal structure without any secondary phase. The average crystallite size obtained from XRD decreases (within the experimental uncertainty) with increased Mn concentration. Magnetic measurements have revealed that Zr 0.98 Mn 0.02 O 2 nanocrystalline sample exhibits both low and room temperature ferromagnetism. The origin of ferromagnetism is attributed to the anionic vacancies created due to Mn doping in ZrO 2. Higher Mn concentrations shows superparamagnetism whereas pure ZrO 2 displayed diamagnetic behavior. The UV–Vis absorption spectra showed a wide absorption peak at 200–330 ?nm, and a redshift was observed in the bandgap with an increase in the concentration of Mn 2+.

A comprehensive understanding of lithium-ion batteries became an essential aspect of solid-state electrochemical research due to their coalescence with routine. While it exhilarates us with increase in productivity of LIBs due to the emergence of Ni-rich cathode materials, the scope to upscale it according to the industrial needs is yet to be tapped to its full potential. Through this perspective article, the functional differences between LIBs and SIBs, state-of-the-art Single-crystalline NCM cathode, the status of the respective research works, crucial factors for industry scaling of the cathode materials, and the future scope of the research work are elucidated.

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Numerous compositions of Er-doped SnO 2 thin films were made at 425?°C on a quartz glass substrate using spray pyrolysis method. The powder X-ray diffraction and X-ray photoelectron spectroscopy analysis confirms the tetragonal phase and surface chemical composition of as made Sn 1-x Er x O 2 (x?=?0.0, 0.01, 0.02, 0.03, 0.04, and 0.05) thin films. The grain size and RMS roughness of the films were estimated from the AFM measurements and the film surface has a saw-tooth-like morphology. The transmission spectra of the films are fallen in the visible range having between 60% and 80% transmittance with different Er concentration. The optical direct, indirect band gap and phonon energy values have been estimated. The photoluminescence measurements under excitation at 325?nm show three distinct emission peaks, a broad hump positioned at 390?nm, two sharp peaks at 420?nm related to tin interstitials, and a sharp peak at 700?nm related to oxygen vacancies. The Er 3+ in SnO 2 increased the oxygen vacancies to maintain charge balance and as a result the intensity of emission peaks increases with Er content.

Hydrothermal method successfully produced a new cesium-metal borate (CsKBO5(OH)·2HO). The crystals are grown in the P2/c space group with a monoclinic lattice, a = 10.7298 (13) Å, b = 8.1521 (11) Å, c = 13.2690 (15) Å, _ = 108.325 (9)°, and Z = 4. The structure is composed of [BO5(OH)]2? groups connected to 8-coordinated potassium, 12- oordinated cesium ions, and water molecules forming the final 3D framework. FTIR and Raman spectra identified the type and nature of the borate groups within the structure. UV-Vis- NIR diffuse reflection spectra have studied the transmission property, whereas TG-DSC analyses revealed the thermal stability of the crystals. In addition, theoretical calculations have been executed to understand the density of states and band structure.

A combination of surface area analyzer and microcalorimetry was employed to investigate the in situ water uptake energetics and the mechanism of proton incorporation in yttrium-doped barium zirconate in the temperature range 200-400 °C. The BaZr1-xYxO3 solid solutions are made with variable yttrium content (x = 10, 20, and 30 mol %) by a controlled oxidant-peroxo synthesis method. The water uptake increases as the partial pressure of water increases; however, no saturation in the hydration isotherm is observed, implying further reaction at higher pH2O. The results suggest three distinct regions of hydration energies as a function of water content. The first water uptake enthalpy values showed high exothermicity, -140, -158, and -157 kJ mol-1 for BaZr1-xYxO3 (x = 10, 20, and 30 mol %), respectively, at 400 °C, and the strong exothermic contribution supports the dissociative incorporation of water. The stepwise in situ hydration energetics is essential to understand the mechanisms of water incorporation and the role of H2O uptake in transport properties.

The formation thermodynamics of YBaCo Zn O (x = 0, 1, and 3) oxides was determined by high-temperature oxide melt solution calorimetry. All of the studied oxides are thermodynamically metastable due to the tendency of cobalt to increase the oxidation state under oxidizing conditions as well as to significant bond valence sum mismatch for Ba and Y in 114-oxides. Complex phase evolution in YBaCo O at 350-400 °C upon oxygen absorption was revealed using incremental precise oxygen dosing. The calorimetric results support phase changes seen during in situ X-ray diffraction structural studies and provide high-resolution measurement of the amount and energetics of oxygen absorbed by YBaCo Zn O under equilibrium conditions.