A large amount of kerf loss waste silicon is generated during the cutting process of photovoltaic silicon wafers, which leads to serious environmental pollution and resource waste. In this work, silicon nitride (Si3N4) composite ceramics were prepared from kerf loss waste silicon by reaction sintering with the addition of Al2O3-Y2O3 at temperatures ranging from 1450 to 1550 degrees C. The effects of additives content and ratio, sintering temperature and dwelling time on open porosity, hardness and dielectric constant of the Si3N4 composite ceramics were investigated. Al2O3-Y2O3 sintering additives will react with the surface silica present on the kerf loss waste silicon particles to form a low melting temperature liquid phase which allows liquid phase sintering to occur and densification of Si3N4 composite ceramics. The results showed that the hardness of the ceramic reached 2.17 GPa, the open porosity was 15.32 % and the dielectric constant was 4.85 when the ratio of Si: Al2O3:Y2O3 was 70:15:15 at the sintering temperature of 1550 degrees C for 16 h. The densification of the sintered products increased and the morphologies changed into bulk-like from fiber-like with the increasing of the temperature from 1450 degrees C to 1550 degrees C. The mechanism of the reaction sintering of kerf loss waste silicon was discussed. This work provides a feasible method to recycle and reuse kerf loss waste silicon for synthesizing the Si3N4 composite ceramics.

The molten salt assisted nitridation process was used in this research to produce Si3N4 composite ceramics from kerf loss silicon waste powder. Na3AlF6 molten salt was introduced into the system and the effects of Si-salt ratio, nitridation temperature on the nitriding product were investigated. These results indicated that Na3AlF6 salt promotes the conversion of waste silicon to Si2N2O, alpha-Si3N4 and beta-Si3N4, and 98.3 % conversion rate of waste silicon was obtained at 1350 degrees C when the silicon-salt ratio was 1:0.75. 90.7 % of Si2N2O phase and 2 %alpha-Si3N4 and 1 %(3-Si3N4 were obtained with the Si-salt ratio of 1:1.5 at 1350 degrees C. The main phase of the product changes from Si2N2O to (3-Si3N4 with the temperature increasing. The content of (3-Si3N4 phase reached 72.9 % with the Si-salt ratio of 1:0.75 at 1450 degrees C. The formation and transformation mechanisms were analyzed combined with the in-situ nitriding process. This work provides a feasible method to recycle the waste silicon powder.

The electrocatalytic co-reduction of CO2 and nitrate (NO3-) presents a sustainable route for urea synthesis, yet it is severely hampered by mismatched activation rates of the two sub-reactions (CO2 reduction reaction and nitrate reduction reaction). Herein, building on our previous study of Ni-BNC for CO2 to CO conversion, we constructed a Ni/Rh nanoalloy catalyst (Ni/Rh-BNC) via Rh-incorporation strategy to effectively redirect reaction pathway to urea from CO. Systematic in situ ATR-SEIRAS and Raman spectroscopy provide mechanistic insights into the intermediate evolution and reaction pathway switching. While Ni acts as a *CO generator, the incorporated Rh species serves a triple regulatory role: (i) activating NO3- to balance the two sub-reaction rates; (ii) stabilizing *CO intermediates generated from adjacent Ni sites via *CO transfer; and (iii) directly initiating C-N coupling to form urea. This Rh-driven *CO “dispatching” mechanism suppresses CO desorption and steers the pathway toward urea formation. Consequently, the urea-to-CO Faradaic efficiency (FE) ratio for Ni/Rh-BNC boosts nearly 30 times than that of Ni-BNC, achieving a urea FE of 31.2% at -0.7V vs. RHE, with a maximum urea yield of 7981.8mg·gmetal-1·h-1 under low metal loading conditions. This strategy underscores a promising blueprint for rational catalyst design of dual metal sites enabling reaction pathway redirection and sub-reaction rate matching for multi-step electrocatalytic reactions.

The electrocatalytic nitrate reduction reaction (NO3RR) has emerged as a sustainable "win-win" strategy for mitigating environmental nitrate (NO3-) pollution while simultaneously synthesizing high-value-added nitrogenous chemicals under ambient conditions. This review provides a comprehensive analysis of recent advancements in NO3RR catalysts, specifically through the lens of reaction mechanism and pathway. We first discuss the pivotal roles of advanced in situ characterization techniques and multi-scale theoretical simulations in capturing reactive intermediates and elucidating the dynamic structural evolution of catalysts at the electrode-electrolyte interface. Regarding ammonia (NH3) synthesis, we emphasize strategies for enhancing nitrate adsorption, balancing activation kinetics at multifunctional sites, and directing the reaction pathway to suppress the competitive hydrogen evolution reaction. For urea production, we examine the co-reduction of nitrate and carbon dioxide (CO2), focusing on the design of catalytic sites that optimize nitrogenous and carbonaceous intermediate adsorption and lower the energy barriers for C-N coupling. Thereafter, the synthesis of high-value chemicals such as amino acids, amides, and nitriles via the "oxime-intermediated" pathway is explored. Furthermore, the integration of data-driven paradigms, including high-throughput screening and machine learning, is highlighted as an emerging frontier for accelerating catalyst screening and uncovering non-intuitive structure-activity relationships. Finally, this review proposes potential directions on addressing critical challenges—such as selectivity-activity trade-offs, long-term stability, and system-level industrial integration—to provide actionable guidance for the rational design for high performance NO3RR electrocatalysts.

The microstructure and mechanical properties of rolled titanium/steel composite plates can be tailored through post-treatment. However, during conventional annealing, the material is usually exposed to high temperatures for prolonged periods. Excessive elemental diffusion and intermetallic compound formation may therefore be induced, leading to interfacial degradation and increased energy consumption. In contrast, mechanical properties can be rapidly improved by pulsed current treatment (PCT), while excessive formation of interfacial compounds can be suppressed. In this study, the tensile deformation behavior of corrugated-rolled titanium/steel composite plates was clarified, and the effects of PCT parameters on their microstructure and mechanical properties were determined. Titanium/steel composite plates were fabricated by corrugated rolling. Their strain distribution and interfacial evolution during tensile deformation were investigated using digital image correlation (DIC) assisted tensile testing. The effects of PCT current density and treatment duration on the microstructure and mechanical properties of the rolled plates were systematically evaluated. It was shown that, as the current density was increased, the interfacial diffusion layer was gradually thickened, recovery and recrystallization were promoted, and the dislocation density was substantially reduced. After PCT at 11.46 A/mm2 for 1 min, a tensile strength of 805.3 MPa and an elongation of 47.03% were achieved in the composite plate. Compared with the as-rolled plate, increases of 4.06% and 8.03%, respectively, were obtained. It is demonstrated by these findings that the strength and ductility of corrugated-rolled titanium/steel composite plates can be simultaneously enhanced by PCT. Therefore, PCT is suggested as a rapid and energy-efficient alternative to conventional annealing.

Two organic molecules, TPA-2Th and TPA-2Py, are developed and serve as self-assembled monolayers (SAMs) for Sb-2(S,Se)(3) (antimony selenosulfide) solar cells. The solid interface interaction between SAMs and Sb-2(S,Se)(3) accomplishes suppressed surface defects, uniform surface potential, suitable interfacial band-bending alignment, efficient charge transfer, and improved photoelectric properties. The optimized solar cells with SAMs show increased power conversion efficiencies (PCEs). For TPA-2Th, the champion PCE is inspiringly enhanced by >10% to 8.21%. This is the first time novel SAMs have been developed specifically for Sb-2(S,Se)(3) solar cells, and this will bring fresh strategies for improving Sb-based solar cells.

Oxygen vacancies (OV) play a crucial role in enhancing the redox properties of catalysts and catalytic performance of selective catalytic reduction (SCR). In this study, OV were self-doped into TiO2 to prepare black TiO2 using the NaBH4 chemical reduction method, and we explore its application as a support material for Mn/Tibased catalysts in low-temperature SCR. In particular, the NaBH4/TiO2 molar ratio and calcination temperature of black TiO2 were systematically optimized to tailor the amount and location of defects (OV and Ti3+), respectively. Consequently, the Mn/1.0Ti-300 catalyst, with a NaBH4/TiO2 molar ratio of 1 and calcined at 300 degrees C, exhibits remarkable nitrogen oxide (NOx) conversion rates of 100 and 70 % at 200 and at 100 degrees C, respectively. Compared with the Mn/0Ti catalyst, Mn/1.0Ti-300 showed 10 % higher NOx conversion at 200 degrees C, further highlighting its excellent NOx removal efficiency in the SCR system. This enhancement was attributed to the reduction of TiO2 at the optimal temperature, which facilitated the formation of surface-localized defects. The abundant surface OV significantly promoted the adsorption and activation of O2 and facilitated the oxidation of MnOx to higher valence states, thereby enhancing the overall redox ability of the catalyst. Consequently, the Mn/1.0Ti-300 catalyst, with abundant Mn4+, OV, and enhanced redox ability, demonstrated superior NOx removal efficiency in low-temperature SCR.

This study provides a comprehensive investigation into the occurrence forms of Sr and its effect on Si purification during Al-30 wt%Si solvent refining, with varying Sr additions. The microstructure of the Al-Si alloy, the impurity content of purified Si, and the precipitation of impurity phases were analyzed using scanning electron microscopy (SEM) and electron probe microanalysis (EPMA), inductively coupled plasma optical emission spectrometry (ICP-OES), and supported by thermodynamic calculations, respectively. Microstructural analysis revealed that Sr modification induced notable morphological changes in the Si phase. The Sr in purified Si is categorized into three distinct forms: (i) Sr atoms that induce Si modification, (ii) Sr atoms dissolved within the Si crystals, and (iii) the P-containing Al2Si2Sr (major). Excessive Sr addition facilitated the significant precipitation of P-rich Al2Si2Sr phases at the solidification front of primary Si. These Al2Si2Sr phases not only reduced the P content (Sr >= 8000 ppmw, tiP >= 87.3 %) in the melt but also interacted with the growing Si crystals at the interface. The high consumption of P in the melt ensures that purified Si can achieve a high P removal efficiency at a rapid cooling rate. Although leaching treatment removed the Al2Si2Sr phases, residual Sr atoms, either dissolved within the Si matrix or incorporated into the Si crystal structure through modifying effects, were largely resistant to removal by such processes. This study provides an alternative perspective for the impurity control of purified Si via Al-Si-Sr solvent refining to produce solar-grade Si (SoG-Si).

Phosphoric acid-doped polybenzimidazole (PA-PBI) membranes are one of the most promising candidates for practical applications in high temperature proton exchange membrane fuel cells. In the field of the proton exchange membranes, a key target is to develop the membranes possessing high proton conducting ability, and meanwhile maintaining good mechanical integrity. It is extremely hard for PBI-based membranes at a high acid doping level (ADL) to have good strength due to the strong "plasticization effect" caused by PA molecules to PBI backbones. In order to obtain high-proton-conductivity membranes with a good comprehensive performance, three imidazole-substituted heteropolyacid salts (imi-HPAs) were synthesized and then incorporated into an arylether-type polybenzimidazole (Ph-PBI) matrix to fabricate some composite membranes via a solution blending process. Since both Ph-PBI matrix and imidazole-substituted heteropolyacid salts contained the functional imidazole groups, some preferred mixed effects and performance enhancements of the organic-inorganic composite membranes were observed. The morphology of the composite membranes revealed that imidazole-substituted heteropolyacid salts were homogenously dispersed in the Ph-PBI matrix. The membrane Ph-PBI/imi-HPA-3-15 % at ADL similar to 290.4 % had the highest conductivity of 166.6 mScm(-1) at 200 degrees C. A H-2/O-2 fuel cell based on one membrane showed a peak power density of 454 mW center dot cm(-2) at 160 degrees C, without humidification.

As a promising thermoelectric material for electronic cooling and power generation, Mg3(Sb,Bi)2 has received extensive attention. Despite efforts to enhance its performance through composite modulation, challenges such as secondary phase refinement, dispersion, and interfacial mismatch, particularly at grain boundaries, remain critical. In this work, by incorporating TiO2-n into the Mg3(Sb,Bi)2-based matrix, the grain boundary phases are in situ engineered, yielding a superior figure of merit (zT) exceeding 2 at 798 K. The electrical conductivity is significantly enhanced with only slight changes to the Seebeck coefficient over the entire temperature range, mainly due to the contribution to carrier concentration and mobility from the newly generated Ti3Sb at grain boundaries. Benefiting from the remarkably enhanced power factor and the diminished lattice thermal conductivity, the zT value shows an overall increase within the temperature range of 300-798 K, leading to a considerable conversion efficiency of 15% for the single-leg device.

Electrocatalytic carbon monoxide reduction reaction (CORR) is a promising strategy for the conversion of CO to high‐value multicarbon products, such as acetate and ethanol. Nevertheless, the activity and selectivity of CO conversion to multicarbon products remain low due to the lack of effective catalysts. Herein, we report the CuO nanoparticles with particle size in the range of 1–8 nm supported on Cu‐MOF, which effectively provides multiple active sites for CORR. The CuO/Cu‐MOF 10 ‐100 exhibited high catalytic performance in acetate production at −0.6 V versus RHE in 1 M KOH aqueous solution, with the maximum Faraday efficiency (FE) of 43% and the partial current density of 6 mA·cm −2 . The CuO/Cu‐MOF 5 ‐100 exhibited higher selectivity in ethanol production with the FE max of 38.1% and the partial current density of 3.7 mA cm −2 .

Water molecules are one of the main impurities in automobile exhaust that will affect the efficiency of three-way catalyst (TWC). Therefore, 600d-Pd@Ce/ACH (the dispersed core-shell active site is obtained by 600 degrees C calcination and loaded with the alkaline-carbonized halloysite support) with great activity and high water-resistance is designed by dispersed treatment and support modification. The result of XPS indicates that 600d-Pd@Ce/ACH with a higher amount of Ce3+ and a lower proportion of Pd2+ facilitate the TWC activity and water-resistance ability, respectively. On the other hand, the catalyst with a certain intensity of hydroxyl groups can enhance the CO oxidation and whole TWC activity, which can be observed in FTIR analysis. Thus, compared to Pd@Ce/ H* (the catalyst without modification; the star symbol (*) indicates that the TWC activity test was conducted in a water-added environment), the T50 of NOx and C3H8 for 600d-Pd@Ce/ACH* decreases by 156 degrees C and 137 degrees C, respectively. Therefore, this research concludes that the generation of functional groups influences TWC mechanisms, leading to competitive adsorption or improved water resistance. Hence, this research provides a promising approach to improve the water-resistance of the core-shell TWC and verifies the reaction mechanism by XPS and FTIR analysis.

In this study, an efficient method for recovery of vanadium (V) from leaching solution of calcium roasting vanadium slag by extraction with di(2-ethylhexyl) phosphate (P204) was proposed. The impact of initial pH value, P204 concentration, contact time, phase ratio (O/A) and temperature on vanadium recovery were analyzed. The effects of stripping agent, O/A, contact time and temperature on the V stripping were analyzed. The maximum V extraction rate was 99.74 % through three-stage extraction under the conditions: 50 % P204, O/A of 1:1, pH of 4.0, 8 min, 30 degrees C. The three-stage maximum vanadium stripping rate was 98.38 % under the conditions of 2.5 M H2SO4 solution, 10 min, 30 degrees C. The purity of the recovered V2O5 was 99.59 % when the pH value was 2.0. The extraction mechanism of vanadium was confirmed as cation exchange mechanism by using Fourier transform infrared spectroscopy.

In this work, Si3N4 powders were prepared by collaborative direct nitriding method from photovoltaic kerf loss silicon waste. The catalytic effect of copper (Cu) on the direct nitriding reaction of photovoltaic Si waste and the morphologies of the nitriding products were investigated. The quantitative analysis of XRD results and thermogravimetric results demonstrate that Cu significantly reduces the initial nitriding temperature, and Cu has a positive effect on the nitriding of silicon waste. At 1300°C, the sample without Cu had almost no nitriding reaction, while the total conversion rate of kerf loss waste Si was 100%, and the yield of (α+β) Si3N4 was up to 79.2% with 8 wt.% Cu additive. The thermodynamic analysis of the Si-O-N-Cu and nitriding process was carried out by FactSage software. Moreover, the morphologies of the nitride products were observed by SEM. The addition of copper promoted the generation of Si3N4 nanorods, and the number and diameter of α-Si3N4 nanorods increased with the increase in copper content. Three reaction mechanisms of Si nitridation were discussed. This work provides a feasible method to reuse and recycle the kerf lost silicon waste.

The pursuit of developing catalysts from earth-abundant materials to supplant those based on precious metals is of paramount importance in selective hydrogenations. While nickel-based systems have shown promise in the selective hydrogenation of butadiene, their practical applications are hampered by severe deactivation issues due to coke deposition and excessive hydrogenation. Here, a novel catalyst, Ni3ZnC0.7@Ni@C, is ingeniously engineered through the controlled oxidation of Ni3ZnC0.7@C. This catalyst is characterized by small Ni0 ensembles elegantly embellishing the Ni3ZnC0.7 nanoparticles, all encased within porous carbon shells. The evolutions of this catalyst, in terms of composition and structure during the oxidation process, is meticulously observed and characterized using a spectrum of advanced techniques. The Ni3ZnC0.7@Ni@C catalyst exhibits outstanding activity and stability in the hydrogenation of butadiene, surpassing other Ni-based systems, including its precursor Ni3ZnC0.7@C and other previously documented catalysts such as Ni3InC0.5 and the Ni3In alloy. A pivotal finding of this research is the self-limiting behavior of coke deposition in the initial reaction stages. This intriguing phenomenon not only curbs further deactivation but also significantly enhances butene production, maintaining operational stability for an impressive duration of 80 hours. This discovery underscores the advantageous role of in situ generated ‘soft’ cokes in augmenting the selectivity and stability of the catalyst, which is particularly enlightening for other catalytic processes that are similarly afflicted by coking issues, thereby opening avenues for further in-depth investigations in this field.

Al-Si dealloying method is widely used to prepare Si anode for alleviating the issues caused by a drastic volume change of Si-based anode. However, this method suffers from the problems of low Si powder yield (<20 wt.% Si) and complicated cooling equipment due to the hindrance of large-size primary Si particles. Here, a new modification strategy to convert primary Si to 2D SiOx nanosheets by introducing a Ca modifier into Al-Si alloy melt is presented. The thermodynamics calculation shows that the primary Si is preferentially converted to CaAl2Si2 intermetallic compound in Al-Si-Ca alloy system. After the dealloying process, the CaAl2Si2 is further converted to 2D SiOx nanosheets, and eutectic Si is converted to 3D Si, thus obtaining the 2D SiOx-3D Si hybrid Si-based materials (HSiBM). Benefiting from the modification effect, the HSiBM anode shows a significantly improved electrochemical performance, which delivers a capacity retention of over 90% after 100 cycles and keeps 98.94% capacity after the rate test. This work exhibits an innovative approach to produce stable Si-based anode through Al-Si dealloying method with a high Si yield and without complicated rapid cooling techniques, which has a certain significance for the scalable production of Si-based anodes.

An InNi 3 C 0.5 -derived InNi 3 alloy is discovered as a coke-resistant low-temperature catalyst for the selective hydrogenation of 1,3-butadiene, affording >90% total yield of butene at 318 K.

Vanadium titanomagnetite (VTM) is a complex polymetallic symbiotic mineral dominated by iron, titanium, and vanadium. Iron extraction from VTM is an issue for the utilization of Vanadium titanomagnetite concentrate. In this work, flotation method combined with magnetic sorting was proposed to separate and recover the iron resources from VTM. The reverse cationic flotation of iron ore in VTM was carried out with polyetheramine (PEA, molecular weight of 2000) as collector, and the differences of iron grade and recovery in VTM with different particle sizes were studied. The magnetic separation result shows that the iron grade of the magnetic part is 28.38