Manufacturing of porous carbon with biomass resources is intensively investigated in recent decades. The diversity of biomass species and great variety of processing methods enable the structural richness of porous carbon as well as their wide applications. This review specifically focuses on the structure of biomass-derived porous carbon either inherited from natural biomass or created by post-treatment. The intrinsic structure of plant biomass is briefly introduced and the utilization of the unique structures at different length-scales is discussed. In term of post-treatment, the structural features of activated carbon by traditional physical and chemical activation are summarized and compared in a wide spectrum of biomass species, statistical analysis is performed to evaluate the effectiveness of different activation methods in creating specific pore structures. The similar pore structure of biomass-derived carbon and coal-derived carbon suggests a promising replacement with more sustainable biomass resources in producing porous carbon. In summary, using biomass as porous carbon precursor endows the flexibility of using its naturally patterned microstructure and the tunability of controlled pore-creation by post-treatment.

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Structural optimization of activated carbon (AC) mainly relies on experience, which depends on the intrinsic structure of biochar, processing conditions, and the interplay of both parties. A fundamental understanding of the pore structure evolution related to the intrinsic structure and composition remains a challenge. In this work, spent mushroom substrate, a rapidly growing byproduct of the mushroom cultivation industry, is used as model biomass to prepare AC under CO2 activation. The structure and composition of the AC products with different activation durations were systematically analyzed with several characterization techniques including N2 adsorption–desorption, scanning electron microscopy, X-ray diffraction, and Raman spectroscopy. A multipeak separation method is developed that enables quantitative analysis of carbonized lignin and carbonized cellulose. A peak area ratio parameter is proposed to describe the retention of cellulose. It is revealed that higher retention of carbonized cellulose corresponds to a larger Brunauer–Emmett–Teller (BET) surface area, demonstrating the dominant role of cellulose in the pore structure development process. This work not only provides a qualitative correlation between cellulose and rich porous structure but also offers a new quantitative tool to understand the structure–composition relationship during the pore evolution process.

It remains a challenge nowadays in the development of highly efficient catalysts for the direct synthesis of H 2 O 2 from H 2 and O 2 . In this work, we developed sulfur-doped carbon-supported Pd catalysts and systematically investigated sulfur effects on catalytic performances through various characterizations (transmission electron microscopy (TEM), N 2 adsorption−desorption, H 2 -temperature-programmed reduction (TPR)/temperature-programmed desorption (TPD), X-ray photoelectron spectroscopy (XPS), etc.). Results showed that sulfur species promoted the in situ formation of Pd nanoparticles and enhanced their dispersion on the supports. Due to the synergistic combination of active metal and support, the catalytic performance has been improved significantly in the direct synthesis of H 2 O 2 . The catalyst doped with the highest sulfur content showed the highest H 2 O 2 productivity of 7148 mmol g Pd −1 h −1 , which was nearly 4 times higher than the catalyst without sulfur doping.

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