| Attapulgite is a naturally occurring one-dimensional nanoscale clay mineral rich in magnesium,aluminum,and silicon.It possesses a unique crystal structure that resembles nanorods and contains nanopores and active surface groups.These distinctive features make attapulgite a valuable raw material for various industries,such as agriculture,chemical engineering,environmental protection,adsorption and separation.This thesis focuses on the development and preparation of new attapulgite-based composites that are environmentally friendly and suitable for use in adsorption and energy storage.The research provides a fresh perspective on how to enhance the value of attapulgite-based clays and supports the development of a new model for utilizing waste clay adsorbents that harmonizes with energy,resources,and the environment.The main outcomes of the research are summarized below:（i）The composition and structure of the attapulgite@carbon composites can be controlled by using“waste”attapulgite after adsorption of tetracycline as raw material.Then the attapulgite@carbon/NiCoLayered double hydroxide composites are synthesized by hydrothermal method and applied to energy storage.The electrochemical properties of the electrode materials can be controlled by varying the amount of attapulgite@carbon.The electrochemical properties of the attapulgite@carbon/NiCoLayered double hydroxide composites prepared under this strategy are significantly enhanced.The composites reached a specific capacity of 2,013.8 F g-1at a current density of 0.5 A g-1,which is four times the specific capacity of NiCoLayered double hydroxide prepared under the same conditions.And while increasing the capacity,it can also improve the retention performance of the material,which remained 79.6%(1,602.2 F g-1)at a high current density of 10 A g-1.The energy storage device with this design strategy has the advantage of high performance and cost-effectiveness in practical applications.In addition,it is important to effectively address antibiotic contamination and recycling of waste adsorbent by this approach.（ii）We successfully synthesized attapulgite@carbon composites via a one-step calcination method using decolorized waste soil,and employed them for the efficient adsorption of Ni2+and Co2+,two major types of heavy metal ions in water bodies.The adsorption capacity of the attapulgite@carbon composites can be regulated by the calcination temperature.The prepared attapulgite@carbon adsorbent exhibited fast adsorption kinetics and broad p H responsiveness,with the maximum adsorption capacities of 108.39 mg g-1 and 91.42 mg g-1 for Ni2+and Co2+,respectively.This strategy holds great potential for the removal of heavy metal ions from water bodies due to its high adsorption performance and low cost.Furthermore,the successful preparation of attapulgite@carbon composites not only offers a reference for the development of adsorbents with high adsorption capacity,rapid adsorption,and easy regeneration but also provides a new path for the sustainable utilization of decolorized waste soil and waste decolorizers.（iii）The attapulgite@carbon/NiCo Layered double hydroxide composites are synthesized by in situ growth in an oil bath method using a waste adsorbent for adsorption of heavy metal ions and applied to energy storage.Structurally analyzed composites were found to have a Ni（OH）2 phase with anα/βintercalation structure,resulting in higher electrochemical reactivity,lower electrochemical reaction impedance,and a higher specific capacity than NiCoLayered double hydroxide prepared under the same conditions.The specific capacity reached 2,114 F g-1 at 0.5 A g-1 and the capacity retention remained 78.1%(1,665 F g-1)at 10 A g-1.This microstructure-based design strategy regulates the electrochemical performance of electrode materials and provides a good reference for the construction of efficient,economical,green,and safe clay mineral-based electrode materials while realizing the high value of natural resources and waste resource utilization. |
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