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The availability of renewable energy resources (e.g., solar, wind, and tides) is crucial for promoting sustainable development and alleviating environmental issues. However, the intermittent nature of renewable energy requires the application of gridlevel electrical-energy storage (EES) technologies to achieve a continuous supply of electricity. As is well known, lithium-ion batteries (LIBs) with high energy density dominate the rechargeable battery market. When faced with the requirements of large-scale power stations, high cost, and limited availability of raw materials, these become serious issues in the application of LIBs. In contrast, sodium-ion batteries (SIBs), which share similar operation mechanisms with LIBs, are considered to be more suitable for grid-level storage due to easy accessibility and geographically available reserves of sodium raw material, with significant improvements in its processing technology made recently. Nevertheless, limited energy density and unsatisfactory cycling life hinder the commercialization of SIBs significantly, which necessitates the use of novel electrode materials with high specific capacities and extended durability. Compared with the accelerated development of cathodes, graphite, on the anode side, as a commercialized anode for LIBs fails to store Na-ions owing to unfavorable thermodynamics. Hence, discovering and designing novel anode materials for SIBs have become a significant challenge. Among different anode materials, phosphorus-based (including phosphides) anodes have been recognized as one of the most promising materials because of their high theoretical capacity (2596 mAh•g −1 for phosphorus) and the abundance of phosphorus resources. Nonetheless, phosphorus-based anodes exhibit low conductivity and large volume expansion, resulting in inferior cycling performance and rating property. Therefore, various strategies, including nanosizing, morphology control, and carbon (noncarbon) modification, have been adopted to improve the performance of phosphorus-based anodes. In this review, the current progress on phosphorus-based anodes for SIBs are summarized. The Na-storage mechanisms of phosphorusbased materials are briefly discussed. Next, strategies for overcoming the disadvantages of phosphorus-based anodes are discussed extensively, including the size and morphology adjustment as well as the carbon (non-carbon) modification. Specifically, the carbon modification not only increases the conductivity but also decreases the volume expansion. Finally, the challenges and perspective of phosphorus-based anodes for SIBs are proposed. In this review paper, the development of suitable anode materials that can help to accelerate the commercialization of SIBs is highlighted.

In the scenario of renewable clean energy gradually replacing fossil energy, grid‐scale energy storage systems are urgently necessary, where Na‐ion batteries (SIBs) could supply crucial support, due to abundant Na raw materials and a similar electrochemical mechanism to Li‐ion batteries. The limited energy density is one of the major challenges hindering the commercialization of SIBs. Alloy‐type anodes with high theoretical capacities provide good opportunities to address this issue. However, these anodes suffer from the large volume expansion and inferior conductivity, which induce rapid capacity fading, poor rate properties, and safety issues. Carbon‐based alloy‐type composites (CAC) have been extensively applied in the effective construction of anodes that improved electrochemical performance, as the carbon component could alleviate the volume change and increase the conductivity. Here, state‐of‐the‐art CAC anode materials applied in SIBs are summarized, including their design principle, characterization, and electrochemical performance. The corresponding alloying mechanism along with its advantages and disadvantages is briefly presented. The crucial roles and working mechanism of the carbon matrix in CAC anodes are discussed in depth. Lastly, the existing challenges and the perspectives are proposed. Such an understanding critically paves the way for tailoring and designing suitable alloy‐type anodes toward practical applications.

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Baking is an energy intensive unit operation. The thermal application of solar energy is getting attention in food processes by eliminating the facts of interrupted supply and fluctuated costs of nonrenewable energy sources. This study has been carried out for the design and development of solar bakery unit which comprises of a 10 m2 Scheffler reflector focusing all the beam radiations on a secondary reflector that further concentrate the beam radiations toward the heat receiver of solar bakery unit to heat up the air circulated through baking chamber employing a photovoltaic operated fan. Computational fluid dynamic (CFD)-based three-dimensional (3D) simulation was performed to analyze the design for uniform air distribution in the baking chamber. The system designed configurations gave quite good results for airflow distribution. The receiver temperature reached between 300 and 400 °C while temperature at the inlet of baking chamber was in the range of 200–230 °C, sufficient for most of the products to be baked. The maximum available solar power at receiver was calculated to be 3.46 kW having an average efficiency of 63%. A series of experiments were conducted for the baking of cakes and total energy available in baking chamber was about 3.29 kW and cake utilized 0.201 kW energy to be baked. The average value of energy utilization ratio was found to be 45%. As a base, the study would lead to the development of an appropriate and low cost solar baking units for the maximum retention of quality parameters and energy saving.

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A novel electrode consisting of a Ti/PbO2 shell and Fe3O4/Sb–SnO2 particles was developed for electrochemical oxidation treatment of wastewater. Scanning electron microscope (SEM), X-ray diffraction (XRD), the current limiting method, toxicity experiments, and high-performance liquid chromatography were adopted to characterize its morphology, crystal structure, electrochemical properties, the toxicity of the wastewater, and hydroxyl radicals. Acid Red G (ARG), a typical azo dye, was additionally used to test the oxidation ability of the electrode. Results indicated that the 2.5D electrode could significantly improve the mass transfer coefficient and •OH content of the 2D electrode, thereby enhancing the decolorization, degradation, and mineralization effect of ARG, and reducing the toxicity of the wastewater. The experiments revealed that, at higher current density, lower dye concentration and higher temperature, the electrochemical oxidation of ARG favored. Under the condition of 50 mA/cm2, 25 °C, and 100 ppm, the ARG, Chemical Oxygen Demand (COD) and Total Organic Carbon (TOC) removal efficiency reached 100%, 65.89%, and 52.52%, respectively, and the energy consumption and the current efficiency were 1.06 kWh/g COD, 8.29%, and energy consumption for TOC and mineralization current efficiency were 3.81 kWh/g COD, 9.01%. Besides, the Fe3O4/Sb–SnO2 particles after electrolysis for 50 h still had remarkable stability. These results indicated that the ARG solution could be adequately removed on the 2.5D electrode, providing an effective method for wastewater treatment.