*2.3. Preparation of TOCNF-CNT@PANI*/*PVA Composite Hydrogel*

Two grams PVA and 100 mL DI water were stirred for 1 h at 90 ◦C to achieve a transparent PVA aqueous solution. Then, the solution was added into TOCNF-CNT, TOCNF-CNT@PANI-1, TOCNF-CNT@PANI-2, and TOCNF-CNT@PANI-3 nanohybrids aqueous dispersion and stirred to form homogeneous dispersion, respectively. According to m (PVA):m (borax) = 4:1, borax powders were added slowly into the mixture with stirring at 90 ◦C until the composite became sticky. The composite showed viscoelastic performance slowly with the decrease of temperature, indicating the formation of the final composite hydrogels. The corresponding hydrogels were named TOCNF-CNT/PVA, TOCNF-CNT@PANI/PVA-1, TOCNF-CNT@PANI/PVA-2, and TOCNF-CNT@PANI/PVA-3, respectively.
