Imaging and spectroscopic techniques for microstructural and compositional analysis of lignocellulosic materials: a review

Application of Infrared Spectroscopy in the Characterization of Lignocellulosic Biomasses Utilized in Wastewater Treatment

“…Yet, several other applications entail the usage of biomass both in the raw format (biomass) or following a thermochemical treatment (biochar or hydrochar). These applications include use of biomass/biochar as an animal feed and fertilizer, for pollutant sequestration for wastewater treatment, and as a substitute for petrochemical-based plastics and, hence, biodegradable packaging [6][7][8][9][10][11][12][13][14][15][16].…”

“…Most importantly, many of these techniques are invasive/ destructive. Wet chemical methods such as hydrolysis using sulfates, alkali, gas chromatography, high performance liquid chromatography, nitrobenzene oxidation, and transesterification are among these conventional approaches [16][17][18][19]. Consequently, finding an effective alternative approach that is cost-effective, non-laborious, and non-invasive for compositional analysis and characterization of the lignocellulosic biomass is important to improve researchers' insights into the structure-propertyperformance relationships.…”

“…Moreover, these techniques are cost-effective, user-friendly, and fast. Several imaging and spectroscopic techniques could be classified under this category, including scanning electron microscopy (SEM), X-ray micro-computed tomography (X-ray μCT), and Fourier transform infrared (FTIR) and near-infrared spectroscopies (NIRS) [16,17].…”

“…In addition, elemental analysis of the surface can also be performed with the energy dispersive X-ray (EDX) aspect. Compared to optical microscopes, SEM has a much higher resolution that could hit 0.01 μm [16,[20][21][22][23]. On the other hand, X-ray μCT depends on the creation of virtual 3D images following the interaction of the X-ray photons with the sample.…”

Cellulose‐based micro‐fibrous materials imaged with a home‐built smartphone microscope

“…Although super‐resolution far field optical microscopic techniques provide significantly improved resolution (Hell, 2007; Iketaki, Watanabe, Bokor, & Fujii, 2006; Kuang, Zhao, & Wang, 2010; Li, Wu, & Chou, 2009; B. Neupane et al, 2015; Puthukodan, Murtezi, Jacak, & Klar, 2020), resolution of traditional optical microscopic systems is lower than that of electron microscopic methods. Nonetheless, different versions of conventional optical microscopic systems are being used in the characterization different fibrous materials (Choong, Yi, & Rutledge, 2015; Hayes & Gammon, 2010; Singh, Lim, & Manickavasagan, 2020). Electron and scanning probe microscopic techniques, depending on the nature of sample, can provide resolution from few nanometer to atomic scale, therefore these techniques are highly used in characterization of diverse materials including micro‐fibrous materials (De Jonge & Ross, 2011; Hörber & Miles, 2003; Lee, Kim, Choi, Takeuchi, & Park, 2017; Venkateshaiah et al, 2020).…”