Additionally, the CNCCr(NO3)3 produced via Cr(NO3)3 system rendered a better thermal stability than that of sulfated CNCH2SO4. This could make the CNCCr(NO3)3 a promising candidate for reinforcing agent and gas-barrier material, as well as providing convenience for polymer applications and processing performed under high temperatures, especially thermoplastics. Oppositely, the introduction of ester groups on the surface CNCH2SO4 could enhance its stability in suspension, which is beneficial for the manufacture of nanocomposites. Unfortunately, the uncontrollable degradation of cellulose into oligomers liquid fraction is a common phenomenon observed from H2SO4 hydrolysis, resulting in a very low yield (~55%). In other words, extra attention is necessary during the process not only due to the highly corrosive acid treatment, most importantly to prevent the acid hydrolysis process going too far. Table 3 displays an exhaustive list of nanocellulose obtained from numerous lignocellulosic biomasses by different hydrolysis techniques, detailing the reaction conditions and presenting the physicochemical properties.