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Thermo-responsive solid amine adsorbents are used for adsorption of CO2 in carbon capture and storage. They have a low temperature regeneration, but are incapable of high CO2 adsorption capacity because of the imbalance between the densities of the amino and thermo-responsive groups. Hence, a novel thermo-responsive hyperbranched intelligent nanofibre-based adsorbent was designed via cross-linking with a hyperbranched polyamine and a thermo-responsive intelligent nanofibre. The liquid–solid phase one-step rapid conversion used here balanced the high amino density (12.40 mmol g−1) with that of the synergistic groups (thermo-sensitive groups, 3.12 mmol g−1, and hydroxyl groups, 4.35 mmol g−1) of the adsorbent. A high-efficiency diffusion kinetics was maintained, and the conversion rate of the reactants reached 99%. An in situ variable-temperature characterisation and density functional theory (DFT) analysis were performed. The adsorbent possessed high CO2 adsorption capacity (6.23 mmol g−1) and ultra-low regeneration temperature (60 °C), the lowest regeneration temperature reported in the literature to date. These were attributed to the specialized and cooperative mechanism between amino, hydroxyl, and thermo-responsive groups of the adsorbent.

Separating the fibers, deconstructing both the interlamellar structures and the intermicrofibrils structures in the cell wall, and cleaving the amorphous regions of cellulose (all reached in one bath chemical-assisted treatment), then extracting cellulose nanofibers (CNFs) from biomass, is both challenging and imperative. A simple, cost-effective and green strategy for extracting CNFs from bamboo using nitric acid and hydrogen peroxide (NCHP), to enable fibrillation via a cooperative mechanism, is demonstrated herein. NCHP-CNFs 13.1 &plusmn, 2.0 nm wide, with a high aspect ratio, 74% crystallinity, excellent UV resistance and high thermal stability, were successfully extracted by treatment in HNO3 aqueous solution, at a concentration of 3.2 mol/L, and treatment with 60.00 mmol/g H2O2 at 50 &deg, C for 48 h. The yields of NCHP-CNFs reached 73% and 99% based on biomass and cellulose, respectively, due to the high delignification selectivity of OH+ and the mild aqueous conditions during the NCHP treatment. These NCHP-CNFs with excellent UV resistance can potentially be applied in the field of UV-resistant coatings, to replace organic and inorganic materials.