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Doping can greatly reduce the lattice thermal conductivity of thermoelectric materials, which is considered as one of the effective ways to improve the thermoelectric properties of thermoelectric materials. First of all, we use the simple and environmentally friendly solution thermal method combined with the tube furnace sintering technology to explore the optimal temperature of sintering Cu2S in the tube furnace. When the sintering temperature reaches 700 °C, we get the thermoelectric value of 0.21. Subsequently, Cu2S thermoelectric materials doped with xmol%Sn (x = 0.5, 1, 3, 5) were prepared and the optimal concentration of Sn was explored. The Sn atom replaces the Cu atom with a smaller radius, greatly reducing the thermal conductivity of the matrix material. In the sample doped with 1%Sn, the total thermal conductivity reaches 0.31 WK−1 m−1, which is 22.5% lower than that of the pure phase sample. In addition, above 623 K, the conductivity of samples doped with 1%Sn is better than that of intrinsic samples, indicating that Sn doping can optimize the conductivity of Cu2S to a certain extent. At 773 K, the ZT of Cu2S + 1 mol%Sn can reach 0.51. 132% higher than undoped Cu2S.This provides a new idea for the preparation and commercial application of Cu–S based thermoelectric materials. [ABSTRACT FROM AUTHOR]

In this article, density functional theory (DFT) was applied to research the structures of γ-Fe2O3 and MFe2O4 (M=Co, Cu, Zn) and to optimize the adsorption models of gases such as CO and NO onto the catalysts. Additionally, the study analyzed the CO oxidation reaction on MFe2O4 (M=Co, Cu, Zn) and the selective catalytic reduction (SCR) reaction of CO + NO in CuFe2O4 and ZnFe2O4. Results showed that CO can effectively adsorb on the reactive substrates, reacting with lattice oxygen to produce CO2 and oxygen vacancies during the CO oxidation process. γ-Fe2O3 (001) required an energy of 0.95 eV to complete the reaction, while CuFe2O4 (100) needed only 0.33 eV, offering better selectivity. In the reaction of CO + NO on CuFe2O4 and ZnFe2O4, NO adsorbed on the surface with double oxygen vacancy to form N2O2 intermediate, then reacted to produce N2 and fill the oxygen vacancy. CuFe2O4 and ZnFe2O4 required energy barriers of 0.68 eV and 0.73 eV, respectively, demonstrating the feasibility of the CO-SCR reaction on the catalyst surface. Further exploration of the reaction in an oxygen-enriched environment found that O2 can inhibit the CO-SCR reaction. The study reveals that MFe2O4 (M=Co, Cu, Zn) catalysts can improve the catalytic activity of the CO oxidation reaction and CO-SCR reaction, with CuFe2O4 exhibiting the best selectivity and catalytic activity. What's more, this study also provides insights for the simultaneous removal of CO and NO. [ABSTRACT FROM AUTHOR]

The catalytic performance of cobalt–chromium spinel NH3-SCR can be enhanced by Mn-doped and Mn–Ti co-doped catalysts; however, there is insufficient understanding of the underlying reaction mechanism. Our work is based on a first-principles computational approach of density functional theory to calculate the optimized configurations of CoAl2O4(100) both before as well as after being Mn-doped and Mn–Ti co-doped. We also simulated the adsorption behavior of gas molecules such as NH3 and NO on the catalyst before and after doping. The optimized configurations and the associated energy distributions for the NH3 dehydrogenation and SCR reactions on Mn0.1Co0.9Al2O4 and Mn0.1Co0.9Ti0.1Al1.9O4 catalysts have undergone a thorough investigation. Our findings demonstrate that the introduction of Mn-doping and Mn–Ti co-doping can enhance the adsorption capacity of gas molecules, such as NH3 and NO, on CoAl2O4 catalysts while significantly reducing the energy barriers for NH3 dehydrogenation and SCR reactions. The performance of Mn–Ti co-doping surpasses that of Mn-doping. Furthermore, we conducted an investigation into the adsorption of H2O and SO2 on the doped catalysts, revealing that Mn–Ti co-doping effectively enhances the water and sulfur resistance properties of the catalysts. Our study is anticipated to serve as a crucial theoretical guide for the development, preparation, and modification of cobalt–aluminum spinel catalysts. [ABSTRACT FROM AUTHOR]

Zinc‐ion hybrid capacitors (ZICs) are of interest for their optimal balance between power and energy density. Among the cathode materials, silicon is particularly attractive due to its abundance and potential compatibility with the microelectronics industry. However, silicon‐based materials exhibit specific capacitances far below 100 mF cm−2 because of their inherently low electronic and ionic transport, making them less competitive than other nanomaterials such as carbon and MXenes. In this study, state‐of‐the‐art silicon‐based ZICs using Mg‐doped porous silicon (PSi) derived from silica aerogels are constructed. The improved electronic conductivity achieved by Mg doping, combined with enhanced ion diffusion promoted by the porous structure, results in excellent electrochemical properties of the ZIC. Consequently, the prepared ZIC exhibits a specific capacitance of 106.1 mF cm−2 at 0.2 mA cm−2 with remarkable cyclic stability (92% retention after 20 000 cycles). Additionally, the pouch ZICs using gel electrolytes demonstrate good rate capability and a long lifespan, indicating significant potential for practical applications. These results underscore the potential of heteroatom‐doped PSi as a cathode for ZICs. [ABSTRACT FROM AUTHOR]

This study utilizes the CGSS2021 dataset to explore institutionalized political engagement among Chinese women. Key findings include positive correlations with social circle involvement, housing area, and traditional media consumption. Interestingly, younger women are less politically engaged. Cross-tabulation reveals that daily social interactions and disagreement with prioritizing marriage over career boost institutionalized political involvement, particularly in Beijing. By contrast, women from Inner Mongolia show the least engagement. Surprisingly, frequent internet usage has limited influence on political participation, whereas traditional media use boosts it. Women in their first marriage also show higher engagement. The study offers policy recommendations to enhance Chinese women's political participation. [ABSTRACT FROM AUTHOR]