Leo 1530vp

The BSA/MWCNTs/GA layer was characterized using an atomic force microscope (AFM, Multimode Nanoscope VIII Instrument, Bruker, Billerica, MA, USA) and scanning electron microscope (SEM, LEO 1530 VP, Zeiss, Oberkochen, Germany). AFM images were obtained under tapping mode in air by using a RTESPA tip (Bruker).

Scanning electron microscopy (SEM) images of miscanthus samples before and after pretreatment were taken to provide qualitative morphological analysis in addition to the chemical analysis of acid soluble lignin and sugars released. These images should provide visual confirmation of any structural changes to lignocellulosic biomass following pretreatment. The samples were dried and coated with gold palladium using a sputter coater (SC7640, Quorum Technologies Ltd) for 180 s at 25 mA for imaging by scanning electron microscopy (LEO 1530VP, Carl‐Zeiss).

The samples were placed upon conductive carbon tape. To enhance the electrical conductivity, the samples were dried and coated with a layer of gold approx. 5 nm thick. The images were taken in standard operation mode with a secondary electron detector by a LEO 1530 VP (Zeiss, Oberkochen, Germany).

Fluorescence spectra were obtained on a Shimadzu RF-7600 fluorescence spectrometer (Hitachi, Tokyo, Japan). UV-Vis absorption spectra were obtained using a TU-1901 spectrophotometer (Beijing general instrument, Beijing, China). Fourier transform infrared (FT-IR) spectra (4000–400 cm⁻¹) in KBr were recorded in a Vector 22 FT-IR spectrophotometer (Bruker, Karlsruhe, Germany). Morphological characterizations were obtained by scanning electron microscope (SEM) (LEO 1530VP, Carl Zeiss, Oberkochen, Germany) with an attached energy-dispersive X-ray spectroscope (EDS). Thermal characterizations were carried out by STA 449 F5 Jupiter Netzsch thermogravimeter (Netzsch, Selb, Germany). Zeta potentials were measured at room temperature in a neutral water solution with a Zetasizer Nano ZS90 (Malvern, Worcestershire, U.K.). Molecular weights and molecular weight distributions were measured by waters 515 gel permeation chromatography (GPC) equipped with a Waters 2414 differential refractive index detector (set at 35 °C) (Waters, Milford, Massachusetts, USA).

SEM images of the samples were obtained by a LEO 1530VP (Zeiss, accelerating voltage of 10 kV).

Morphologies of the deposit patterns were captured by scanning electron microscopy (LEO 1530VP, Zeiss, Oberkochen, Germany). Fluorescence images of the deposit patterns were captured by optical fluorescence microscopy (BX51, Olympus, Tokyo, Japan). All images were acquired in similar illumination conditions and acquisition settings. They are displayed without any post-processing.

Pretreated and raw α-cellulose samples were visualised using SEM. SEM images allow inspection of the surface morphology and could provide an insight into how the structure has been affected by the pretreatment. Samples were sputter coated (SC7640, Quorum Technologies Ltd) with gold palladium for 180 s at 25 mA before imaging with SEM (LEO 1530 V P, Carl Zeiss Ltd) using an excitation voltage of 20 KV and an aperture of 30 μm.