In this study, within a hydrothermal system, graphene oxide was used as the reaction precursor, ammonium sulfate and glutamic acid were selected as heteroatom sources, reducing agents, and functional reagents. Meanwhile, nanocellulose extracted from agricultural waste corn stover was utilized as a physical spacer and an ion transport carrier. Thus, nanocellulose/N, S co-doped graphene composites with hierarchical porous morphology, high packing density, and a large number of heteroatomic groups were successfully constructed. Among them, the aqueous symmetric supercapacitors with the composites as electrode materials deliver good gravimetric/volumetric capacitance characteristics(290.3 F g-1 and 409.4 F cm-3), high energy density (10.1 Wh kg-1 and 14.2 Wh L-1), satisfactory rate capacity, and long cycle life. Furthermore, by introducing KOH, nanocellulose, and graphene oxide into the polyvinyl alcohol matrix, a new gel electrolyte was prepared. Due to the penetration of nanocellulose and graphene sheet throughout the entire system, the flexible solid-state supercapacitors based on the new gel electrolyte and the composites exhibits high specific capacitance (228.5 F g-1), good rate performance (84.0 %), and remarkable mechanical properties. In summary, the samples and electrolyte prepared in this study are suitable for supercapacitors.

During the industrial silicon refining process, impurities can affect the selectivity and activity of organic silicon monomer synthesis. This study utilized the simplified molecular interaction volume model (MIVM) alongside actual production data and samples to investigate the effects of different aluminum concentrations on typical impurity phases in industrial silicon. et al. concentrations of 1500-1600 ppmw, the Si7Al8Fe5 phase emerges. As the Al concentration increases to 1700 ppmw, the Si2Al3Fe phase forms. The FeSi2, Si8Al6Fe4Ca, and FeTiSi2 phases are consistently present in industrial silicon. MIVM predictions indicate that the activities of Fe, Ti, and Ca increase with increasing Al concentration, consistent with the actual production trend. However, production data suggest that this correlation is limited under certain conditions. Moreover, MIVM is used to predict the interactions among impurities in industrial silicon. The effects of Al concentration on typical impurity phases in industrial silicon are elucidated using MIVM combined with actual production data. Proper control of Al concentration facilitates the efficient synthesis of organosilicon monomers, increases their yield, and reduces energy consumption. These findings provide a theoretical and technical basis for controlling impurities in organosilicon monomer synthesis.

The volume of retired photovoltaic (PV) modules has been increasing rapidly, with the recovery of metallic silver representing one of the key aspects for the effective recycling of these modules. However, conventional processes for the separation and recovery of metallic silver face several challenges, including the use of toxic leaching reagents, poor selectivity, and contamination from extraneous metal impurities during the reduction step. This study proposes a strategy for the clean, short-path recovery of high-purity silver through selective leaching and reduction. This method is based on the reaction between methanesulfonic acid (MSA, CH3SO3H) and ascorbic acid (C6H8O6, vitamin C) under acidic conditions, yielding methanesulfonic acid hydroxide (CH3SO3OOH). The latter further dissociates to form the reactive oxygen anion HSO5- and hydrogen peroxide, utilising the synergistic effect between these two species. Simultaneously, the oxidative properties of oxyanions are leveraged to accelerate the leaching process, thereby enhancing the reaction rate. Compared to traditional methods, the leaching rate is doubled. Moreover, C6H8O6 is employed to reduce Ag+, avoiding the introduction of metal impurities associated with conventional displacement reactions and thereby enhancing the purity of the recovered silver. By optimizing the leaching and reduction processes, both the recovery yield (> 99.7%) and purity (> 99.6%) of silver can be achieved, which are significantly superior to those reported in current metallic silver recovery methods. The successful implementation of this strategy provides a novel route for the green and efficient separation and recovery of metallic silver from retired PV modules.

Room temperature vulcanized silicone rubber (RTV) crosslinked with conventional silane agents often suffers from limited thermal stability and mechanical properties. To address this issue, a novel phosphazene-silane hybrid crosslinking agent (HC-PD-KH) was synthesized from a phosphazene derivative and 3-glycidyloxypropyl-trimethoxysilane (KH-560) via epoxy ring-opening reaction. HC-PD-KH was used as a crosslinking agent to prepare RTV with hydroxy terminated polydimethylsiloxane (PDMS) matrix in the presence of an organotin catalyst. Comprehensive characterization revealed remarkable performance improvements: TGA showed significantly enhanced thermal stability compared with KH-560 systems, the 10% weight loss temperature (T10) rose from 385.7 degrees C to 444.5 degrees C, the char yield at 800 degrees C rose dramatically from 1.2% to 11.4%; DMA and tensile tests demonstrated higher damping properties, tensile strength and modulus: the tensile strength and elongation at break reached 1.26 MPa and 200%; water contact angle measurements indicated improved hydrophobicity, with the water contact angle increasing from 93.5 degrees to 103.4 degrees. These enhancements are attributed to the rigid backbone of phosphazene rings and phenyl groups, the contribution of polar N-H moieties, and the uniform dispersion of HC-PD-KH within the silicone matrix. This study provides a promising strategy for the molecular design and crosslinking of high-performance RTV.

This study uses red mud and phosphogypsum as the main raw materials, supplemented with sodium silicate and sodium bicarbonate, to prepare non-fired ceramic granules with adsorption properties. The disintegration rate of the non-fired ceramic granules was taken as the evaluation index, and response surface methodology was employed to investigate the effects of the contents of red mud, phosphogypsum, sodium silicate, and sodium bicarbonate on this index. The optimized mixing proportions of red mud, phosphogypsum, sodium bicarbonate, and sodium silicate are 70

The clean and efficient utilization of semi-coke (SC) offers substantial significant social benefits. In this study, SC was employed as the primary feedstock to investigate the effects of particle size and blending with different carbon-based reducing agents on reactivity under a carbon dioxide atmosphere. In addition, SC was blended with carbonaceous reducing agents commonly used in industrial silicon smelting at mass ratios of 9:1, 8:2, 7:3, 6:4, and 5:5 to evaluate the reactivity evolution of the blended materials. Kinetic and thermodynamic analyses, together with reactive index evaluation, were used to track the changes in reaction activity. The structural evolution of the blended samples subjected to different temperature treatments was characterized through Fourier transform infrared spectroscopy, X-ray diffraction, Raman spectroscopy, and scanning electron microscopy. The results demonstrated that decreasing particle size enhanced SC reactivity. Furthermore, when SC was blended with low-rank non-coking coal or charcoal, the reactivity indices of the mixtures exhibited an overall increasing trend as the blending ratio increased from 9:1 to 5:5, accompanied by a continuous reduction in activation energy. The activation energy of the 5:5 mixture decreased by 10.90

Metallurgical batching—governing raw material proportioning across sintering, blast furnace ironmaking, converter steelmaking, and non-ferrous smelting—critically determines product quality, energy consumption, and production cost throughout the full process chain. Its inherent complexity, characterized by strong nonlinear physicochemical coupling, measurement delays of up to 1.5 h, and multi-source raw material disturbances, renders conventional linear programming and empirical methods inadequate for dynamic, multi-objective industrial environments. This review systematically examines 98 representative studies (2020–2026) on intelligent algorithms applied to metallurgical batching optimization. A two-dimensional analysis framework of the fusion algorithm function and metallurgical scene is established. All kinds of methods are divided into three categories: prediction-oriented, optimization-oriented and decision-oriented, covering four typical scenes of sintering burdening, blast furnace ironmaking, converter steelmaking and non-ferrous metal smelting. Traditional machine learning models achieve sintering burn-through point prediction with R2 ≈ 0.85 and offer superior interpretability via SHAP analysis. Deep learning architectures deliver blast furnace silicon content prediction with RMSE ≈ 0.04%, while multi-objective evolutionary algorithms provide mature Pareto optimization for batching cost and carbon objectives. Reinforcement learning holds long-term potential for closed-loop adaptive control but remains constrained by Sim-to-Real safety barriers. Converter steelmaking and non-ferrous smelting are identified as underexplored domains. Three priority directions are proposed: domain-adaptive predictive modeling for cross-plant generalization, real-time re-optimization embedding mechanism constraints, and safe reinforcement learning transfer via high-fidelity digital twins.

The reaction characteristics of metallic impurities in metallurgical grade silicon (MG-Si) significantly influence the efficiency of trichlorosilane (TCS) synthesis, a key process for the photovoltaic industry. This study elucidates the migration and evolution of these impurities using multi-scale characterization and thermodynamic calculations. We reveal that the primary impurities (Fe, Al, Ca, Ti) exist not as elements but as intermetallic compounds, including FeSi2, Si7Al8Fe5, Si8Al6Fe4Ca, and TiFeSi2. During synthesis, the migration of these elements is governed by the boiling points of their respective chlorides. Consequently, low-boiling-point chlorides (Al2Cl6 and TiCl4) volatilize with the gaseous TCS, while high-boiling-point chlorides (FeCl2 and CaCl2) cause Ca and Fe to be retained in the solid spent contact mass. The transformation follows a multi-step pathway: Intermetallic Compound → FeSi Intermediate Phase → Metal Chlorides, with unreacted FeSi also remaining in the solid residue. Furthermore, the retained FeCl2 readily oxidizes to high-valence oxides upon air exposure after collection. This work establishes a new mechanistic framework for impurity behavior, focusing on the evolution of intermetallic.

The efficient separation of silicon from metallurgical-grade silicon refining slag (MGSRS) is essential for enhancing resource recovery and promoting environmental sustainability. Conventional separation techniques, including flotation and pyrometallurgy, are often hindered by high energy consumption, process complexity, and inefficient separation. These limitations are primarily attributable to the high viscosity of the slag and strong interfacial bonding. This study proposes a novel water quenching technique to improve the separation efficiency of silicon from slag. The method enhances separation performance by leveraging the amorphous transformation of the slag phase and the associated surface tension effects. The experimental procedure involved subjecting metallurgical grade silicon refining slag (MGSRS) to three distinct cooling treatments: direct remelting slow cooling (DRSC), crucible quenching (CQ), and melt quenching (MQ). The results indicate that the water quenching method effectively achieves silicon/slag separation. The melt quenching (MQ) treatment significantly promotes slag amorphization through rapid cooling. This mechanism of action reduces the thickness of the interfacial diffusion layer from 8.2 mu m to 3.6 mu m and decreases the interfacial bonding strength by 60-70 %. Thermodynamic calculations performed using the Butler equation and FactSage software indicate that at 1923 K, a substantial surface tension difference exists between molten silicon (700-750 mN & sdot;m- 1) and the CaO-Al2O3SiO2 slag system (486 mN & sdot;m- 1). This difference drives the coalescence and separation of silicon. The MQ process achieves effective partial separation of silicon from slag with low energy consumption. This method offers a promising short-loop route for silicon recovery from metallurgical grade silicon refining slag (MGSRS), thereby advancing green metallurgical waste treatment.

The conventional thermal treatment of common quartz often proves insufficient for the thorough removal of fluid inclusions, thereby hindering the production of high-purity quartz sand. In this study, a novel stepwise chlorination roasting process is proposed, utilizing the bursting temperature characteristics of fluid inclusions in quartz along with the benefits of chlorination roasting. Vein quartz was initially roasted at 600 degrees C for 2 h in a Cl2 atmosphere, followed by a second roasting at 900 degrees C for an additional 2 h. Experimental results indicate that, after stepwise chlorination roasting, the light transmittance of quartz increased from 56.72% to 93.38%, while water content decreased from 222.60 mu g/g to 64.00 mu g/g, corresponding to a removal rate of 71.25%, surpassing conventional methods in eliminating fluid inclusions. The final water content is lower than that of first-grade crystal, indicating compliance with standards for use in photovoltaic quartz crucibles. By analyzing the mechanisms of quartz crack propagation and lattice transformation, the mechanism by which stepwise chlorination roasting enhances the removal of fluid inclusion impurities has been elucidated. This study presents a new method of removing fluid inclusions from ordinary quartz, which will contribute to the healthy and sustainable development of the photovoltaic industry.

The substantial waste (similar to 35 %) of high-purity silicon generated as diamond wire sawing silicon waste (DSSW) during photovoltaic silicon wafer production necessitates efficient reutilization. To address this challenge, composite silicon nanomaterials were synthesized via a facile metal-assisted chemical etching (MACE) method. Comprehensive characterization (XRD, XPS, UV-Vis, SEM, HRTEM) revealed a unique visible-light-responsive porous/sheet-like heterostructure (Cu2ONPS/PSi/SiNSs). This one-step MACE process yielded a 43 % enhancement in specific surface area (37.9 m(2) g(-1) versus DSSW's 26.5 m(2) g(-1)) and induced quantum confinement effect, broadening the bandgap to 1.37 eV (from the initial DSSW value of 1.12 eV). These structural and electronic modifications facilitated exceptional photocatalytic hydrogen evolution, achieving an initial rate of 1408.3 mu mol g(-1) h(-1) and a sustained average rate of 2319.4 mu mol g(-1) h(-1) over 6 h. The corresponding solar-to-hydrogen (STH) conversion efficiency reached 0.76 %, with an apparent quantum yield (AQY) of 7.5 %. Importantly, Cu2O concentration was demonstrated to critically influence composite morphology and photocatalytic performance. This work bridges the photovoltaic and hydrogen energy sectors, presenting a high-value reutilization pathway for DSSW and demonstrating an efficient strategy for solar hydrogen production.

Achieving the synergy between efficient light trapping and excellent interface passivation are desired in terms of surface texturing of high-efficiency silicon solar cell technology. To address these issues, this study proposed a Cu-Fe bimetal-assisted chemical etching (Cu-Fe MACE) method to texture the surface of silicon wafers. The effects of Fe(NO3)3 concentration on Cu deposition behavior, as well as the influence of Cu deposition on the subsequent etching process, were systematically investigated. The results indicated that the Fe(NO3)3 concentration had a pronounced influence on the deposition morphology of nano-sized Cu and the corresponding etching behavior. By controlling the Fe(NO3)3 concentration in the range of 0.1-0.15 M, a uniform texture of ballcrown-shaped upright pyramids was obtained on n-type monocrystalline silicon, showing good uniformity and light-trapping capability, with the average reflectance in the 300-1100 nm wavelength range reduced from about 25% for the as-cut wafer to 13% under the optimized conditions. By combining PL and minority carrier lifetime measurements, the passivation behavior of the etched surfaces was investigated. The rounded tips and smoother surface of the ball-crown-shaped upright pyramids significantly improved the coverage continuity and film quality of the Al2O3 passivation layer. Compared with conventional upright pyramids, the new textured structure exhibited a higher minority carrier lifetime (tau eff approximate to 3.0 & times; 10-4 s at an injection level of 1015 cm-3) and an implied open-circuit voltage of about 715 mV. This work provided valuable guidance for the design and application of surface texturing strategies that enabled both excellent light trapping and strong passivation in crystalline silicon solar cells.

With the increasing number of retired photovoltaic (PV) modules, their efficient recycling has emerged as a vital research focus. In this study, a green CuCl2-ChCl solvent system was developed to recover silver (Ag) from retired photovoltaic modules. Ultrasonic intensification combined with mechanical stirring resulted in a high Ag leaching rate of 98.81 %. Kinetic analysis revealed that the Ag leaching process in the solvent system was controlled by a chemical reaction mechanism, with an apparent activation energy of 42.19 kJ/mol. An experimental model was established and optimized using response surface methodology to determine the optimal process parameters. The morphology and elemental distribution of samples before and after leaching were analyzed via scanning electron microscopy and energy-dispersive X-ray spectroscopy. AgCl was formed using HCl and NaCl as chlorine sources and then reduced to metallic Ag by ascorbic acid. The reduction process yielded Ag powder with a recovery rate of 98.57 %. This study provides a sustainable and efficient approach for recycling Ag from retired PV modules.

Industrial silicon is a critical raw material for the photovoltaic and electronic information industries. However, current secondary refining processes still face challenges in the effective removal of Ti impurities. During pure-oxygen refining, the Ti content increases and exhibits a strong correlation with Al and Ca removal. This study systematically investigates the effects of Al and Ca on Ti evolution during O2-H2O(g) refining through industrial production analysis data, laboratory experiments, electron probe microanalysis, and first-principles calculations. Ti removal efficiency is negatively correlated with the initial Al and Ca contents. For raw materials with high Al and Ca contents, Ti removal efficiency is below 15% but exceeds 67% for raw materials with low Al and Ca contents. Microstructural analysis reveals that under high- Al and high-Ca conditions, Ti forms stable tau 5-(Fe,Ti)Si2 intermetallic compounds, which hinder its removal. Under low-Al and low-Ca conditions, the independent precipitation of Ti is suppressed, which facilitates its oxidation removal. First-principles density functional theory (DFT) calculations further indicate that Al and Ca inhibit Ti hydroxylation through electronicstructure modulation and competitive OH adsorption, respectively. This study establishes a cross-scale correlation between raw-material composition and atomic-scale interactions and providing theoretical guidance for targeted Ti removal during industrial silicon refining.

This study investigated the correlation between carbon structure evolution and resistivity at high temperatures, with a focus on designing composite coal reducing agents for industrial silicon smelting. Binary and ternary composite coal systems were produced using non-coking coal (NC), medium-coking coal (MC), and high-coking coal (HC) as feedstocks. Their resistivity was investigated at ambient and elevated temperatures, as well as their coke yield, carbon structure evolution, reaction kinetics, and pyrolysis product composition. The results indicated that the resistivity of the samples followed the order NC > NMH > NM > NH > MC > HC. The resistivity of the composite coal systems was significantly lower than the theoretical weighted average of the individual coal types. This indicated the presence of a synergistic resistance reduction, which was confirmed by thermogravimetric (TG) analysis. As the temperature increased between 700-900 degrees C, the resistivity decreased sharply and then stabilized from 900 to 1200 degrees C due to changes in carbon's structural order. X-ray diffraction (XRD) and Raman spectroscopy revealed that higher temperatures decreased the carbon interlayer spacing (d002) and increased the microcrystal dimensions (Lc and La) and degree of graphitization. The combination of these factors improved the electrical conductivity of the coal samples. Fourier-transform infrared (FTIR) spectroscopy and pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS) indicated significantly different functional group changes and volatile product release between the different coal types during pyrolysis, which also influenced their ability to form conductive networks. This work reveals for the synergistic resistance reduction mechanism in composite coal systems, offering a new strategy for optimizing reducing agent formulations.

This study performed kinetic and thermodynamic analyses on samples of multigranular low-rank unbound coal (LNC) with three different particle size ranges: 40-80 mesh, 80-150 mesh, and 150-300 mesh. The study investigated the pyrolytic coke yield of multigranular LNC and its reaction characteristics under a CO2 atmosphere. The synergistic effect of particle size and coke properties on the reactivity was highlighted using a combination of characterization techniques (BET, SEM, XRD, Raman, and FTIR) and the Friedman, KissingerAkahira-Sunose, Flynn-Wall-Ozawa, and Starink methods. The results showed that reducing the particle size significantly increased the specific surface area and pore volume of the coal samples. Upon increasing the pyrolysis temperature, the coke yield decreased from 91.2-93.64 wt% at 300 degrees C to 64.8-66.92 wt% at 900 degrees C. The fine-grained samples had slightly lower yields because they underwent more thorough volatilization. At the same temperature, the 'D/'G values of the fine-grained samples (150-300 mesh) were significantly higher than those of the coarse-grained samples, and they also exhibited greater reactivity. Their gasification reaction index (GRI), comprehensive pyrolysis index (CPI), and comprehensive gasification characteristic index (S) values were respectively 0.77 %, 20.21 %, and 31.36 % higher than those of the coarse-grained samples (40-80 mesh). The kinetic analysis indicated that the average activation energy (Ea) of the fine-grained samples was 169.19 kJ/mol, which was significantly lower than that of the coarse-grained samples. The reaction mechanism was dominated by diffusion and nucleation, and Delta H, Delta G, and Delta S confirmed that the fine-grained samples were more reactive. This study provides guidance for optimizing the particle size during the classification and utilization of low-rank coal to regulate the coke yield for the large-scale application of CO2.

Y0.15Zr0.85O1.93 (YSZ) has emerged as a crucial solid electrolyte material for modern solid oxide fuel cells (SOFCs) and oxygen sensors, prized for its exceptionally high oxygen ionic conductivity. However, further enhancement of its oxygen ionic conductivity is essential to optimize SOFCs energy efficiency and mitigate high-temperature electrode degradation. Despite extensive efforts involving various doping strategies, this critical challenge remains unsolved. To address this issue, a novel YSZ-LSGM heterostructure composite electrolyte was developed by adding a minor La0.9Sr0.1Ga0.8Mg0.2O2.85 (LSGM) phase into the YSZ phase, and its performance as an electrolyte was systematically evaluated. LSGM's high ionic conductivity promotes rapid oxygen ion transport across grain boundaries. The heterogeneous interface between YSZ and LSGM also favors oxygen ion transport, significantly enhancing both the grain boundary conductivity and the total ionic conductivity of the heterostructure composite. Remarkably, the YSZ-30 wt% LSGM composite demonstrates approximately 8 times in total conductivity (0.0008 S/cm at 750 degrees C) compared to pure YSZ (0.0001 S/cm at 750 degrees C). Most strikingly, the YSZ-30 wt% LSGM's grain boundary conductivity is around 24 times higher than the YSZ electrolyte's. These findings highlight the synergistic advantages of the heterostructure composite electrolyte, which combines the excellent compatibility of YSZ with the superior ionic conductivity of LSGM. This study not only provides a promising strategy for developing advanced composite electrolyte materials but also opens a new avenue for further research in high-performance SOFC technologies. (c) 2025 Chinese Society of Rare Earths. Published by Elsevier B.V.

In this study, a green synthesis method based on photovoltaic industry waste was developed and used to prepare silicon carbide nanowires (SiC@SiO2NW) with excellent wave absorption performance. Core-shell SiC@SiO2NW were controllably synthesized in the temperature range of 1250-1550 degrees C by chemical vapor deposition using photovoltaic waste graphite as the growth substrate and silicon cutting waste and microsilica powder as the silicon sources. Structural characterization showed that SiC@SiO2NW had a SiO2-coated SiC NW morphology, and the wire diameters were uniformly distributed within the range of 100-200 nm. Electromagnetic performance tests showed that the samples prepared at 1550 degrees C exhibited the best microwave absorption characteristics. When the matching thickness was 1.48 mm, a strong reflection loss of -46.44 dB was achieved at 11.54 GHz, and a wideband effective absorption of 4.84 GHz was also obtained. This wave absorption performance was due to the enhanced dielectric loss brought about by the unique core-shell structure of the material. This research achieved the high-value utilization of photovoltaic waste, which provides new ideas for developing new wave-absorbing materials and opens up a new green path for the reutilization of industrial solid waste.

Red mud (RM), a by-product produced during the extraction of alumina from bauxite, requires high-value utilization to mitigate environmental risks and promote resource circulation. In this study, RM was used as a functional modifier to synthesize RM-modified poly(heptazine imide)-type crystalline carbon nitride composites (RM-PHI) via thermal polycondensation in a molten NaCl system. The adsorption performance of RM-PHI toward methylene blue (MB), along with optimal conditions and underlying mechanisms, was systematically investigated. The incorporation of RM effectively tailored the pore structure and surface chemical environment, enhancing interfacial activity while preserving the intrinsic PHI framework. Among the samples, 4RM-PHI exhibited the best performance, achieving a removal efficiency of 99.08%. Isotherm fitting further showed that the maximum adsorption capacity derived from the Langmuir model reached 771.62 mg·g−1. Kinetic and isotherm analyses indicate that the adsorption process follows pseudo-second-order kinetics and the Langmuir model, suggesting a spontaneous and exothermic monolayer chemisorption process. Combined with pore structure analysis, FTIR, and XPS results, RM modification was found to promote the formation of mesoporous structures and introduce abundant oxygen-containing active sites, thereby strengthening electrostatic attraction, π-π interactions, hydrogen bonding, and ion exchange. The composite maintained over 80% removal efficiency after five regeneration cycles, demonstrating good stability and reusability. Overall, this work promotes the high-value ‘waste-to-wealth’ utilization of RM and provides an efficient novel MB adsorbent for dye wastewater purification.