Carbon materials have been widely used in designing supercapacitors (SCs) but the capacitance is not ideal. Herein, we synthesize polyaniline (PANI) nanotubes on the basis of a carbon cloth (CC) through a one-step self-degradation template method, and fabricate a CC@PANI NTs-H (CC@PANI nanotubes doping at high temperature) composite electrode by thermal acid doping. The CC@PANI NTs-H electrode obviously exhibits better electrochemical performance with a gravimetric capacitance of 438 F g −1 and maintains 86.8% after 10,000 cycles than the CC@PANI NTs-R (CC@PANI nanotubes doping at room temperature) electrode. Furthermore, we assemble a flexible solid state supercapacitor (FSSC) device with the as-prepared CC@PANI NTs-H composite electrodes, showing good flexibility and outstanding electrochemical performances with a high gravimetric capacitance of 247 F g −1 , a large energy density of 21.9 Wh kg −1 , and a capacitance retention of 85.4% after 10,000 charge and discharge cycles. Our work proposes a novel and easy pathway to fabricate low-cost FSSCs for the development of energy storage devices.

Saline soil stabilization is being increasingly applied in foundation treatment engineering. Chloride saline soil obtained from sites and laboratory-made chloride soil (ZS) with various NaCl concentrations prepared artificially were stabilized using alkali-activated slag (AS). A series of unconfined compressive strength (UCS) tests, X-ray diffraction (XRD), energy-dispersive X-ray analysis (EDXA), thermal gravity-differential thermal gravity (TG-DTG), and ion concentration tests were conducted to investigate the strength variation and mechanism of the AS-stabilized chloride saline soils. The results showed that NaCl has a significant influence on the strength of AS-stabilized chloride saline soil and the strength of AS-stabilized ZS (GZS) increases with increase of chloride content in soil samples. Friedel's salt (Fs) and NaOH are generated by the reaction of NaCl and CaO·Al 2 O 3 (CA) in the slag in the GZS. Fs can fill the pores in stabilized soil, and NaOH can promote calcium silicate hydrate (CSH) generation. These two effects combine to enhance the strength of GZS. The relationship between the rate of increase of 28-d UCS of AS-stabilized chloride saline soil and the chloride content in soil was obtained through regression analysis of the increase of UCS of GZS.

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