Compact Sn/C composite realizes long-life sodium-ion batteries

Sodium-ion batteries are considered as a promising low-cost alternative to commercial lithium-ion batteries.However,the harsh preparation conditions and unsatisfactory electrochemical performance of most sodium-ion batteries anode materials limit their commercial applications.Herein,we develop a new alloying/dealloying method for producing nano-scale tin from freezing point to room temperature.Due to the unique surface properties of tin particles,a tin/carbon composite with a compact structure is obtained.When coupled with a diglyme-based electrolyte,tin/carbon composite(contains 60 wt.%tin)exhibits a reversible capacity of 334.8 mAh·g^(−1)after 1,000 cycles at 500 mA·g^(−1).An as-prepared tin/carbon anode||high-load vanadium phosphate sodium full cell(N/P ratio:1.07)shows a stable cycle life of 300 cycles at 1 A·g^(−1).The achievement of such an excellent performance can be ascribed to the carbon conductive network and robust solid electrolyte interphase film,which facilitates the fast transportation of electrons and Na ions.This work provides a new idea to prepare other alloyed anode materials for highperformance sodium-ion batteries.

Effects of nitrogen and salt on growth and physiological characteristics of processing tomato under drip irrigation

Xinjiang of China is one of the three largest planting bases of processing tomato in the world,but soil salinization has restricted the production of tomato processing.In order to study the effects of soil nitrogen,salt and their interaction on growth and physiological characteristics of processing tomato under drip irrigation,different amount of nitrogen fertilizer were added to reconcile different salt stress to explore the response mechanisms of growth and yield of processing tomato to soil nitrogen and salt contents with a two-year experiments.The results showed that the effects of soil salinity on the growth and physiological characteristics of processing tomato were significantly greater than that of input of nitrogen fertilizers.The higher soil salt content(≥5.0 g/kg)significantly inhibited the growth of processing tomato.The increase in addition of nitrogen fertilizer could alleviate the salt inhibition and promote the growth of processed tomato with the increase of soil salt content,and the maximum nitrogen application rate was 300 kg/hm2.The linear plus platform was selected to determine the nitrogen effect models of non-saline-alkali soil and weak saline-alkali soil,but the square root nitrogen effect model of moderate saline-alkali soil was selected to accurately predict the yield of processing tomato.It was suggested that the processing tomatoes should be planted in moderate saline-alkali soil to achieve higher yields due to lower input of nitrogen fertilizer,potentially reducing fertilizer costs and maximizing profits from high processing tomato yields.The results have a strong guiding significance for planting of processing tomato on saline-alkali land and appropriate fertilization to increase the yield of processing tomato.