Fig. 1: The freezing behaviors of THF solution on the GOs anchored glass substrates.
a Schematic depiction of the THF/water solution deposited on the substrate anchored with GO nanosheets. The blue volume represents the drop of THF solution and the contact area between liquid drop and solid substrate is marked in the yellow circle. b shows the AFM images of 38 nm GOs (average lateral size) anchored on the substrate with the scaled coverage n = 0.18 × 1 (relative GO graft density times scaled contact area). Scale bar, 100 nm. c shows the corresponding height profiles through the cross-section along the marked lines. d, e Optical microscopy observation of the formation of THF clathrate (needle-like crystals, step 3) and ice (black and block-like substance, step 5) on the GO anchored surface under microscope in cooling (d) then heating (e) stages. Cooling rate, 1 °C min−1. Sample volume, 3.5 μL; the scaled contact area of solution drop, S = 1 in the unit S0 = 0.25 mm2; scale bar, 100 μm. f Thermal analysis of the formation and melting of THF clathrate hydrates and ice on the glass substrate surface without (red line) and with (gray line) the anchored 38 nm GO nanosheets by DSC.
