Application of Novel Batteries of TM-doped Nitride-based Materials towards Clean Energy Storage: A DFT Study

Enhanced electrochemical performance of MgFeO4 spinel as anode materials for Lithium-ion batteries through manganese doping

ABSTRACTThe hypothesis of the energy adsorption phenomenon was confirmed by density distributions of CDD, TDOS, and LOL for GaN and ternary alloys of AlGaN and InGaN. Based on TDOS, the excessive growth technique on doping manganese is a potential approach to designing high‐efficiency hybrid semipolar gallium nitride–based devices in a long wavelength zone. A vaster jointed area engaged by an isosurface map for Mn doping GaN, AlGaN, and InGaN toward formation of nanocomposites of Mn@GaN–H, Mn@AlGaN–H, and Mn@InGaN–H after hydrogen adsorption due to labeling atoms of N(4), Mn(5), and H (18), respectively. Therefore, it can be considered that manganese in the functionalized Mn@GaN, Mn@AlGaN, or Mn@InGaN might have more impressive sensitivity for admitting the electrons in the status of hydrogen adsorption. Furthermore, Mn@GaN, Mn@AlGaN, or Mn@InGaN are potentially advantageous for certain high‐frequency applications requiring batteries for energy storage. The advantages of manganese over GaN, AlGaN, or InGaN include its higher electron and hole mobility, allowing manganese doping devices to operate at higher frequencies than nondoping devices. A comprehensive investigation on hydrogen grabbing by heteroclusters of Mn‐doped GaN, AlGaN, and InGaN was carried out using DFT computations. The position of the Mn‐doped energy states was evaluated via the spectra obtained from the bipolar devices with the Mn‐doped GaN/AlGaN/InGaN as an active layer.

ABSTRACTWe report on the growth and magnetic properties of single crystal Mn-doped GaN, InGaN, and AlGaN films. The III-Nitride films were grown by MOCVD, while the Mn doping was performed by solid-state diffusion of a surface Mn layer deposited by pulsed laser ablation. Mn-doped InxGa1-xN films were grown with x < 0.15, where the easy axis of magnetization rotates from in-plane to out-of-plane by changing the InxGa1-xN thickness/strain-state of the film from compressively strained to relaxed. Mn-doped AlxGa1-xN films were grown with x < 0.40 showing ferromagnetic behavior above room temperature. SQUID measurements ruled out superparamagnetism within these films. By optimizing the growth and annealing conditions of Mn-doped III-Nitrides, we have achieved Curie temperatures in the range of 228 to 500K. These ferromagnetic Mn-doped III-Nitride films exhibit hysteresis with a coercivity of 100–500 Oe. TEM analysis showed no secondary phases within these films.

The International Conference on Clean Energy Science(ICCES) held every three years provides a forum for scientists and engineers to discuss the most recent developments in clean energy, and promoting international collaborations to identify and address challenges in the area. This paper briefly summarizes the work on clean energy and energy storage reported in the 2nd International Conference on Clean Energy Science(2nd ICCES) held in Qingdao, China, April 13—16, 2014. Solar energy conversion, photocatalysis and environmental catalysis, electrochemical energy conversion and storage remain hot topics. Clean coal and fossil fuels technologies, biofuels and biomass conversion, bio and bio-inspired systems for energy conversion are seen to become new hotspots of research. CO2 capture, storage and utilization, hydrogen production and storage are still seen to be growing areas. Materials and nanotechnology for energy systems remain key areas for resolving some clean energy and energy storage related challenges.

Stacking fault disorder induced by Mn doping in Ni(OH)2 for supercapacitor electrodes

Lead magnesium niobate (PMN)–lead titanate (PT) solid solution with composition 0.675 PMN–0.325PT has been obtained with manganese (Mn) doping in various ratios. The effect of Mn on the electrical properties was examined in detail using dry-pressed samples produced from PMN–PT powders synthesized by a solid-state calcination route. Based on the results, 0.7 mol.% was selected as the optimum Mn doping ratio to enhance the soft properties and figure of merit (FOM). Random and textured PMN–PT plates for use in energy harvesting applications were then prepared by a tape-casting method. Samples were textured using 1 vol.% plate-like barium titanate (BaTiO3, BT) template. The calculated FOM of random samples fabricated by tape-casting increased from 8469 × 10−15 m2/N to 11,273 × 10−15 m2/N with Mn doping, in parallel with observations in dry-pressed samples. The FOM of textured PMN–PT was found to be as high as ∼ 25,999 × 10−15 m2/N and increased to ∼ 31,720 × 10−15 m2/N for textured Mn-doped PMN–PT. The Curie temperature (Tc) of samples obtained by tape-casting was measured to be 160°C. The electromechanical properties of the samples were also studied in detail, and property matrices calculated using resonance methods are reported for all compositions.

Charging time and energy storage rate analysis of fin effect inside the horizontal tube for thermal energy storage

The effect of Mn concentration on the optical properties of Mn-doped layers grown by metalorganic vapor phase epitaxy is investigated. The Mn-doped GaN layers exhibite a typical transmittance spectrum with a distinct dip around 820 nm which is attributed to the transition of electrons between the edge of valence band and the Mn-related states within the bandgap. In addition, electroluminescence (EL) spectra obtained from the bipolar devices with Mn-doped GaN active layer also show that considerable Mn-related energy states existed in the bandgap. The position of the Mn-related energy states in the GaN is first evaluated via EL spectra. In addition to the absorption of band edge, the Mn-related energy states behaving like an intermediate band cause an additional sub-band gap absorption. Consequently, the fabricated GaN-based solar cells using Mn-doed GaN as the absorption layer exhibit photocurrent higher than the control devices without Mn doping. Under one-sun air mass 1.5 G testing condition, the short-circuit current of the Mn-doed GaN solar cells can be enhanced by a magnitude of 10 times compared with the cells without Mn doping.

Recently, two-dimensional materials have been attracting increasing attention because of their novel properties and promising applications. However, the impurity doping remains a significant challenge owing to the lack of the doping strategy in the atomically thin layers. Here we report on the chromium (Cr) and manganese (Mn) doping in atomically-thin crystals grown by chemical vapor deposition. The Cr/Mn doped samples are characterized by a peak at 1.76 and 1.79 eV in photoluminescence spectra, respectively, compared with the undoped one at 1.85 eV. The field-effect transistor (FET) devices based on the Mn doping show a higher threshold voltage than that of the pure while the Cr doping exhibits the opposite behavior. Importantly, the carrier concentration in these samples displays a remarkable difference arising from the doping effect, consistent with the evolution of the FET performance. The temperature-dependent conductivity measurements further demonstrate a large variation in activation energy. The successful incorporation of the Mn and Cr impurities into the monolayer paves the way towards the high Curie temperature two-dimensional dilute magnetic semiconductors.

The promising frontier for next-generation energy storage and clean energy production: A review on synthesis and applications of MXenes

With the increasing demand for energy, finding clean, efficient, and renewable energy storage solutions is a crucial focus in today's world. In this context, potassium-ion batteries have garnered widespread research and attention as an essential solution to address environmental pollution and future energy challenges. This paper focuses on one of the key components of potassium-ion batteries - the anode materials, with a special emphasis on plasma-doped carbon-based anode materials. Initially, the significance of carbon-based anode materials in ion batteries is introduced. Subsequently, a detailed exploration is conducted on the diverse applications of plasma-doped carbon-based anode materials in lithium-ion, sodium-ion, and potassium-ion batteries. These materials demonstrate excellent electrochemical performance, significantly improving the energy density, cycle life, and stability of the batteries. Looking ahead, we will additionally discuss the optimization of synthesis methods, further enhancement of electrochemical properties, and the prospective development of large-scale production techniques. Finally, the study underscores the potential of plasma-doped carbon-based anode materials to emerge as a new trend in the field of future energy storage, making a substantial contribution to advancing sustainable energy storage technologies.

Lithium-ion batteries (LIBs), the most successful secondary battery in the energy storage field, have been deeply and widely used in all aspects of life (such as transportation commuting, electronic products, and clean energy storage), but the development of the most commercially successful battery is in crisis due to the problems of high cost and resource shortage. Sodium has attracted attention in energy storage because of its rich resources and low price. However, sodium ions have a larger ion radius compared with LIBs, which results in worse ionic conductivity. Therefore, this characteristic of sodium ions has become an important factor restricting the development of sodium-storage electrode materials. Whereas the restriction of developing electrode materials in sodium-ion batteries (SIBs), the emphasis of research has focused on enhancing the electrochemical performance of high-performance anode and cathode materials and promoting the commercial application of SIBs. This paper will introduce the current research status and progress in cathode and anode materials of SIBs, and the future development direction of cathode and anode materials for SIBs will be summarized by analyzing the mechanism and defects of related electrode materials.

Atomic doping of clusters is known as an effective approach to stabilize or modify the structures and properties of resulting doped clusters. We herein report the effect of manganese (Mn) doping on the structure evolution of small-sized boron (B) clusters. The global minimum structures of both neutral and charged Mn doped B cluster (n = 10–20 and Q = 0, ±1) have been proposed through extensive first-principles swarm-intelligence based structure searches. It is found that Mn doping has significantly modified the grow behaviors of B clusters, leading to two novel structural transitions from planar to tubular and then to cage-like B structures in both neutral and charged species. Half-sandwich-type structures are most favorable for small (n ⩽ 13) clusters and gradually transform to Mn-centered double-ring tubular structures at clusters with superior thermodynamic stabilities compared with their neighbors. Most strikingly, endohedral cages become the ground-state structures for larger (n ⩾ 19) clusters, among which adopts a highly symmetric structure with superior thermodynamic stability and a large HOMO-LUMO gap of 4.53 eV. The unique stability of the endohedral cage is attributed to the geometric fit and formation of 18-electron closed-shell configuration. The results significantly advance our understanding about the structure and bonding of B-based clusters and strongly suggest transition-metal doping as a viable route to synthesize intriguing B-based nanomaterials.

Effects of manganese doping on properties of sol–gel derived biphasic calcium phosphate ceramics

Herein, a facile co‐precipitation technique was employed to prepare cobalt oxide (Co3O4) and Co3O4 nanoparticles (NPs) with manganese (Mn) doping. The morphologies and crystalline structures of the as‐prepared NPs were characterized by X‐ray diffraction (XRD), Fourier‐transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), differential thermal analysis (DTA), thermogravimetric analysis (TGA), and Brunauer–Emmett–Teller (BET) techniques. XRD measurements showed that Co3O4 (19.42 nm) and Mn‐doped Co3O4 (14.02 nm) NPs were successfully synthesized on average, and they exhibit a face‐centered cubic crystalline structure. The SEM images also depicted the spherical morphology of Co3O4 NPs, with Mn particles clustering together. FTIR spectroscopy further confirmed the presence of Mn within the doped Co3O4 NPs. TGA/DTA analysis revealed boosted thermal stability in Mn‐doped Co3O4 NPs compared to Co3O4 NPs. Moreover, the BET surface areas of Co3O4 and Mn‐doped Co3O4 NPs were 534.013 and 712.741 m2/g, respectively, indicating an increase in surface area due to Mn doping. Consequently, Mn doping enhances both surface area and thermal stability, rendering Mn‐doped Co3O4 NPs desirable for nanomaterial applications. This study shows that modulating the Mn doping concentration in the Co3O4 NPs offers superior surface area and thermal stability compared to the prepared Co3O4 NPs.