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Bimetallic sulfides offer high theoretical specific capacitance and good stability as electrode materials due to their diverse redox reactions, larger specific surface areas, and better conductivity. The morphology of the electrode material is an important influencing factor for the electrochemical properties. Herein, a series of ZnCoS electrode materials with different morphologies were prepared by varying the solvent in the solvothermal reaction, and the effects of different microstructures on the electrochemical properties of ZnCoS were investigated. The ratio of water and ethanol in the solvent was controlled to modulate the microstructure of the as-prepared ZnCoS materials. XRD and XPS revealed the physical and chemical structure of the ZnCoS materials. SEM and TEM observations showed that the microstructure of ZnCoS transformed from one-dimensional wires to two-dimensional sheets with increasing amounts of ethanol. The maximum specific capacitance of the as-prepared ZnCoS materials is 6.22 F cm−2 at a current density of 5 mA cm−2, which is superior to that of most previously reported bimetallic sulfides. The enhanced electrochemical performance could be ascribed to its sheet-assembled spherical structure, which not only shortens the path of ion diffusion but also increases the contact between surface active sites and the electrolyte. Moreover, the spherical structure provides numerous void spaces for buffering the volume expansion and penetration of the electrolyte, which would be favorable for electrochemical reactions. Furthermore, the ZnCoS electrodes were coupled with activated carbon (AC) electrodes to build asymmetric supercapacitors (ASCs). The ASC device exhibits a maximum energy density of 0.124 mWh cm−2 under a power density of 2.1 mW cm−2. Moreover, even under a high-power density of 21 mW cm−2, the energy density can still reach 0.055 mWh cm−2. [ABSTRACT FROM AUTHOR]

To investigate the effects of biochar on the quality improvement of tobacco planting soil and tobacco production, a field experiment with 5 treatments: T0, 0 t/hm² biochar + 0.64 t/hm² nitrogen fertilizer; T1, 0.5 t/hm² biochar+0.64 t/hm² nitrogen fertilizer; T2, 1 t/hm² biochar+0.64 t/hm² nitrogen fertilizer; T3, 1.5 t/hm² biochar+0.64 t/hm² nitrogen fertilizer; T4, 2 t/hm² biochar+0.64 t/hm² nitrogen fertilizer was conducted. The effects of biochar on the carbon emission and organic carbon components of tobacco planting soils and tobacco physiological indexes were analyzed. The results showed that: 1) Compared with treatment T0, treatments T1, T2 and T3 reduced the total soil carbon emission by 28.14%, 25.25% and 8.41% respectively; and treatment T4 raised the total soil carbon emission by 8.79%. 2) The biochar treatments increased the contents (mass fractions) of soil total organic carbon, microbial biomass carbon, soluble organic carbon and easily oxidized organic carbon. On the 70th day after transplanting, the total organic carbon and microbial biomass carbon in soils of treatment T4 were 19.38% and 29.38% higher than those of treatment T0. The proportion of microbial biomass carbon in total organic carbon decreased, while the proportion of soluble organic carbon in total organic carbon increased with the application of biochar. 3) The biochar treatments promoted tobacco root vigor, the photosynthetic characteristics of tobacco leaves and the dry matter accumulation in tobacco plants. Among them, treatment T3 increased tobacco root vigor by 80.43% comparing with treatment T0. Therefore, suitable biochar applications can reduce soil carbon emission, increase contents of different soil carbon components, promote the root growth and development, photosynthetic characteristics and dry matter accumulation of tobacco plants. [ABSTRACT FROM AUTHOR]