Bottom-up hydrothermal carbonization for the precise engineering of carbon materials

Hydrothermal carbonization (HTC) of carbohydrates in general has been reported as a sustainable and green technique to produce novel carbon materials. Traditional HTC of carbohydrates leads to irregular carbonaceous particles with low porosity due to inevitable aggregation induced by the high surface energy and the failure of classical templates. The accrescent understanding of the reaction mechanism in the HTC "dark box" provides possibilities of engineering HTC carbonaceous materials in a refined way. In the past decades, some unprecedented carbonaceous structures were achieved via modified HTC processes. Those progresses reflect the mightiness of HTC for precise synthesis however the last specialized review on this topic is over a decade old. In this review, we summarize the advances in the precise engineering of carbonaceous materials with specific morphologies and structures by the bottom-up HTC of carbohydrates, especially mono-saccharides and disaccharides. This review elucidates the HTC set screws for the shaping of and/ or the pore-creation within the targeted nanostructured carbonaceous materials. The benefits for applications arised from the special control of HTC carbon are also discussed. This review could inspire further insight into the HTC process and broader application of carbon nanostructures made from renewable resources.