Preparation And Supercapacitance Characterization Of Halloysite Nanotube Composites

Halloysite nanotubes own a sea of advantages such as rich reserves,non-toxic,large specific surface area,special functional group structure et al.Although halloysite nanotubes are applied widely in catalyst support,few studies are concentrated on the electrode material.Both metal sulfide and layered double hydroxide can perform excellent Faraday pseudocapacitance,however,the aggregation problem affects their electrochemical performance seriously.Furthermore,PEDOT possess outstanding electrochemical properties and stability,turning into the ideal supercapacitor electrode materials in recent years.The paper prepared dibasic or ternary composites using halloysite nanotubes as substrate material,aiming at the development of the electrode material with high specific capacitance and excellent cycling stability.The main details are as follows:1.The Ni₃S₂/HNTs@HS composite was prepared via hydrothermal reaction using halloysite nanotube modified by KH-590 as substrate material.In the three-electrode system,a specific capacitance of 2253 F g-1 at the current density of 1 A g-1 was obtained and kept at least 82.6%after 2000 cycles.In the two-electrode system,the specific capacitance also reached 325 F g-1.2.An innoxious and low-cost soft chemistry method was used to synthesize the HNTs@NiMn-LDH and H-HNTs@NiMn-LDH composite.Finally,the H-HNTs@NiMn-LDH composite electrode get a high capacitance performance with the specific capacitance of 1665 F g-1 at the current density of 1 A g-1 in three-electrode system,better than the HNTs@NiMn-LDH composite electrode.In the two-electrode system,the H-HNTs@NiMn-LDH composite electrode performed a specific capacitance of 152 F g-1.3.The modified halloysite nanotube and EDOT were used as substrate material and polymer monomer respectively on the preparation of H-HNTs@PEDOT,and then the H-HNTs@PEDOT@NiMn-LDH composite was synthesized via the loading of NiMn-LDH.The electrochemical analysis demonstrated that the composite had a specific capacitance of 1808 F g-1 at the current density of 1 A g-1 and the capacitance reserved 81.8%after 2000 cycles,which owned a better capacitance performance than H-HNTs@NiMn-LDH.