Materials Science for Energy Technologies最新文献

Biomass waste candlenut shells, such as adsorbent carbon, can be utilized. Fe₃O₄ has great electrical conductivity, and ZIF-67 has diverse pores. Activated carbon, Fe₃O₄, and ZIF-67 were prepared to obtain a combination of these materials using the co-precipitation method. FTIR spectra show a peak at 1341 cm⁻¹, which depicts the Fe-O bending vibration. At peak 1558 cm⁻¹ shows C = N streching. The top of 1412 cm⁻¹ and 991 cm⁻¹ extend the full ring. The sp² aromatic peak may be seen at 1150 cm^-1C-H bond. The surface area is 17.76 m²/g, and the pore size is 14.99 nm. Coercivity is 119.63 Oe, which shows a strong magnet. The highlight of the study was activated carbon from biomass waste candlenut shells (Aleurites moluccana) doped ZIF-67 supported Fe₃O₄ with specific capacitance shows high. The diffusion percentage shows fewer electrolyte ions entering the active material, and resistance also showed low results. It can increase the percentage of capacitive ions, thus improving the electrode. Electrochemical results show 1335F/g of high specific capacity at 1 A/g current density. It indicates a suitable candidate material for supercapacitor electrodes.

Methylene blue dye is still widely used as a clothing dye in the textile industry. Therefore, it is necessary to process this dye waste before it enters water bodies so that it does not damage the environment. The aim of this research was to optimize the function of magnetite (Fe₃O₄) extracted from iron sand combined with TiO₂ for degrading methylene blue dye. The iron sand was extracted using a bar magnet, sieved, washed, milled, and dried. Iron sand (20 g) was converted into magnetite using the co-precipitation method with a stirring speed of 800 rpm at a temperature of 80 °C for 30 min. Magnetite was mixed with TiO₂ with 30 % ethanol using a mechanical stirring method. The characteristics of Fe₃O₄-TiO₂ photocatalyst were tested using XRD, SEM-EDX and VSM. According to the XRD data, the crystal size of the Fe₃O₄-TiO₂ photocatalyst was below 40 nm. The presence of Fe and Ti in the photocatalyst material and their even distribution were determined by SEM-EDX testing. Through VSM, it was confirmed that soft magnetic properties were present in this material. The performance of the Fe₃O₄-TiO₂ photocatalyst in the degradation of methylene blue dye was analyzed using a UV–Vis spectrophotometer. The test results showed that the performance of the photocatalyst improved as the contact time increased and was marked by a decrease in the optical absorption intensity; the best performance of the Fe₃O₄-TiO₂ photocatalyst reached 93 %. Therefore, it can be concluded that iron sand as part of the photocatalyst material, play a role in the photodegradation of methylene blue dye.

The present study deals with developing biochar from the waste biomass using slow pyrolysis at dynamic temperatures (400, 600, and 800 °C) and holding times (30, 45, and 60 min). The produced biochars were characterized by their thermal, physical, and chemical properties. The biomass characterization confirmed its candidacy for being used as a biochar feedstock. An XRF study of ash content confirmed that biomass has a lower possibility of slagging and fouling issues. A kinetic study of biomass confirmed that activation energy increased substantially (34.37–90.34 and 22.74–63.92 kJ mol⁻¹ for MWS and CNW, respectively) by varying the reaction order. The outcomes of the pyrolysis process revealed that elevating the pyrolysis temperature from 400 to 800 °C resulted in a decrease in the yield of biochar, accompanied by an increase in its carbon content. XRD study of biochar established that rising pyrolysis temperature caused a change in the mineral content of biochar. HHV and bulk density of biochar were found to be increased by increasing pyrolysis temperature from 400–800 °C. Moreover, it was observed that BET surface area and Zeta potential increased as the pyrolysis temperature rose from 400–800 °C. FE-SEM study of biochar, established by increasing temperature from 400–800 °C, accelerated the volatilization activity and caused a considerable surface modification in the resulting biochar. Overall, biochar displayed various mineralogical compositions, surface alteration, high thermal stability, carbon content, and pH, making them appropriate for strengthening the procedures of different industrial applications.

With the help of a hydrothermal process, we were able to prepare vertically layered MoS₂ nanoflakes that were rooted to TiO₂ modified. MoS₂ nanoflakes and TiO₂ contribute significantly to the strong XRD peaks and μ-Raman spectroscopy, and this phenomenon may also be explained by the unique structure of vertically stacked MoS₂ nanoflakes on TiO₂ that has many exposed edges and large surfaces as well as high electron transfer rates between TiO₂ and MoS₂. As can be clearly seen, there are no noticeable changes in the self-photodegradation of MB under visible light interaction (VLI), and the MoS₂ doped TiO₂ photocatalyst displays ∼ 90 % degradation efficiency. By, measuring photoelectrochemically, charge carriers are separated efficiently. These experiments illustrate the transient photocurrent response of the MoS₂ doped TiO₂ photocatalyst while cycling between three on/off cycles. As a result of a low recombination rate of the photoexcited charge carriers, the MoS₂ doped TiO₂ photocatalyst displays superior photocurrent response. In other words, a lower charge transfer resistance results in a faster transfer of charge between the surfaces.

This research aims to provide an efficient and cost-effective renewable energy supply. It assesses the potential for photovoltaic (PV) and hydro energy in Pirthala, Haryana, India, using HOMER Pro® v3.14.2. A Hybrid renewable energy system (HRES) can continuously power 855 homes. The optimal HRES configuration comprises well-optimized PV modules, hydro turbines, converters, and batteries. The top four configurations were selected based on criteria such as net present cost (NPC) and cost of energy production (COE). The most effective HRES configuration involves a 3461-kW solar array, a 98.1 kW hydro turbine, 304 lithium-ion batteries of 100 kWh, and a 2785-kW converter, achieving a 100 % integration of renewable energy. This ideal HRES was thoroughly assessed regarding economic, technical, and renewable energy considerations. The results and the optimized HRES configuration can serve as a valuable reference for similar initiatives in rural areas, contributing to adopting renewable energy sources and enhancing energy access and reliability.

Titanium dioxide (TiO₂) nanoparticles are commonly used as photoanode materials in dye-sensitized solar cells (DSSC). The structure of TiO₂ can be modified by doping to enhance its optical and electrical performance. The modification carried out in this research was by providing Ag doping on TiO₂. Silver (Ag) added to TiO₂ is convinced to reduce the recombination and increase the energy level of the photo-excited electrons from the TiO₂ conduction band. Ag-doped TiO₂ was carried out by a simple mixing method. The microstructure of Ag-doped TiO₂ was successfully characterized by XRD and SEM. The absorbance of the Ag-doped TiO₂ thin films was measured by UV–Vis spectroscopy, confirming the optimum energy gap of 3.09 eV and resulting in the best PCE of 6.31 %.

This paper deals with the synthesis and properties of new ternary mixed Cd1-xBexTe (cadmium beryllium telluride) crystal-based electrodes for photovoltaic cells which is a modified version of dye- sensitized solar cells. We determined the thermal stability and photovoltaic performance of the obtained devices. Cd1-xBexTe crystals are grown using the Bridgman technique at high temperatures and pressure for different compositions. Using the modified doctor blade method, we fabricated dye-sensitized solar cells (DSSC) using Cd1-xBexTe-based film as working electrodes. The mixed crystals with the highest beryllium content (10 %) and the lowest (1 %) are used. At the same time, the counter electrode and polymer electrolytes are common. Comparative studies with standard DSSC are also undertaken to compare the stability and charge mechanism. As prepared, DSSC using ternary Cd1-xBexTe showed efficiency as high as 3.11 % at 1 sun condition. The life span measurement indicated promising results, and DSSC is stable up to 720 h with a reasonable decrease in fill factor from 84 to 55.

In this study, the influence of p-type doping with Na atoms on the optical bandgap and electrical conductivity of a series of bismuth ferrites (BiFeO₃) synthesized by a low-cost solid-state method was evaluated. To identify the properties that influenced the bandgap and electrical response of the samples, the phase of interest was identified and quantified by X-ray diffraction (XRD), the morphological characteristics were determined by scanning electron microscopy (SEM). Structural properties were elucidated by spectroscopic techniques and finally the optical response (indirect bandgap) was measured by ultraviolet–visible spectroscopy (UV–Vis) and electrical response (conductivity) by solid-state electrochemical impedance spectroscopy (SS-IES). The results of this work demonstrated that the optical and electrical response of the series of Na-doped BiFeO₃ samples is dependent on at least eight structural and morphological variables (sodium ratio, purity, unit cell volume, oxygen vacancy concentration, crystalline domain size, structural microdeformations, particle size and Warburg-type resistive phenomena). Among the most relevant results, the influence of purity, intrinsic and physical defects was identified, observing a decrease of the electrical resistance and energy gap with the presence of Na.

The solid-state zinc-ion battery (ZIB) is environmentally friendly, cost effective, and extremely safe, which are essential features for alternative sustainable energy storage systems. Herein, a polymer composite electrolyte (PCE) is successfully developed through a facile solution-casting approach from a thermo-responsive copolymer-based electrolyte and layered ternary carbide (Ti₃AlC₂). The thermo-responsive copolymer demonstrated synergistic mechanical properties through the addition of an appropriate plasticizer and a zinc salt. This combination suggests that the material possesses thermal self-protection capabilities due to its anti-Arrhenius ionic-conducting behavior. However, parasitic reactions and dendrite formation hindered the achievement of its full potential. The incorporation of Ti₃AlC₂ or MAX phase can mitigate the above obstacles, enhancing electrochemical performance with excellent flexibility and maintainable self-extinguishing. The solid-state ZIB benefits from the well-designed PCE with the expanding layer interspacing, delivering a remarkably high capacity (336 mAh g⁻¹ at 0.1 A g⁻¹) and energy density of 242 Wh kg⁻¹. This is achieved due to the Ti₃AlC₂′s ability to immobilize or entrap triflate anions via electrostatic forces. Therefore, the designed PCE is a promising step toward the development of flexible solid electrolytes in ZIBs.

Manganese dioxide-multiwall carbon nanotube (MnO₂-MWCNT) nanocomposites were synthesized via one-pot synthesis method with varying concentrations of 1 mg/ml, 4 mg/ml, and 10 mg/ml MWCNT. The synthesized nanocomposites were characterized using x-ray diffraction (XRD), transmission electron microscopy (TEM), and electrochemical measurements. The intent of studying different concentrations is, ultimately, to correlate the effect of the concentration of multiwall carbon nanotube on the electrochemical performance of the MnO₂-MWCNT nanocomposites_. Two primary phenomena were observed as CNT concentration increased. First, less crystalline MnO₂ adsorption onto individual CNTs occurred. Subsequently, CNT agglomeration became the primary feature of the nanostructures of high CNT concentration. The electrochemical studies reveal that the specific capacitance of MnO₂ increases from 124 F/g to 145 F/g by the addition of 1 mg/ml MWCNTs and decreases to 102 F/g for MnO₂-10 mg/ml MWCNT nanocomposite.