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The exploration of renewable, cost-effective, and environmentally friendly electrode materials with high adsorption, fast ion/electron transport, and tunable surface chemistry is urgently needed for the development of next-generation biocompatible energy-storage devices. In recent years, biomass-derived carbon electrode materials for energy storage have attracted significant attention because of their widespread availability, renewable nature, and low cost. More importantly, their inherent uniform and precise biological structures can be utilized as templates for fabricating electrode materials with controlled and well-defined geometries. Meanwhile, the basic elements of biomass are carbon, sulfur, nitrogen, and phosphorus. The special naturally ordered hierarchical structures as well as abundant surface properties of biomass-derived carbon materials are compatible with electrochemical reaction processes such as ion transfer and diffusion. To date, a series of novel porous carbon materials with different dimensions have been prepared by various methods using biomass as the raw material, which is an important field in the fabrication of supercapacitor electrode materials. Herein, we summarized recently reported biomass-derived carbon materials with one-dimensional, two-dimensional, and three-dimensional structures and their applications as carbon-based electrode materials for supercapacitors. Finally, the current challenges and future perspectives of the carbon-based electrode materials with respect to the supercapacitor's performance were closely highlighted.

BiOBr photocatalysts were prepared by a facile one-pot solvothermal approach with cetyltriethylammnonium bromide and bismuth nitrate as the precursors in ethanol, ethylene glycol, tert-butanol, benzyl alcohol, and 2-methoxyethanol solvents, respectively. The morphology, pore structure, specific surface areas, and optical properties of BiOBr are solvent dependent, and a possible formation mechanism for the thin BiOBr nanosheets prepared in benzyl alcohol with higher exposed (001) facet is proposed. BiOBr prepared in benzyl alcohol exhibited superior photocatalytic activity for the photodegradation of Rhodamine B under visible light irradiation, and the high photocatalytic performance can be ascribed to the nanosheet structure and increased number of exposed (001) surfaces. The photogenerated holes h+ and superoxide radical anions ˙O2− have a major effect on RhB degradation via photocatalysis and dye self-sensitization. This work provides a simple method to prepare BiOBr with a nanosheet structure and more exposed (001) surfaces, which motivates its practical application for the exploitation and utilization of solar energy.

Herein, a series of SAPO-11 molecular sieves were modified by citric acid and hydrochloric acid. They were characterized by ICP, XRD, SEM, N2 adsorption–desorption, NH3-TPD, 29Si MAS NMR, and Py-IR and evaluated by the methylation of naphthalene with methanol to 2,6-dimethylnaphthalene (2,6-DMN). According to the XRD results, hydrochloric acid at a high concentration not only removed extra-framework aluminum but also deleted framework silicon; this resulted in the formation of crystal defects. N2 adsorption–desorption results showed that all the samples possessed micropores and secondary mesopores. The SAPO-11 sample modified with 4 mol L−1 hydrochloric acid for 30 min exhibited the largest secondary mesopore size distributions. NH3-TPD and 29Si MAS NMR showed that hydrochloric acid at a high concentration could eliminate more acid sites. SAPO-11 modified with 4 mol L−1 hydrochloric acid for 30 min presented high catalytic performance for the methylation of naphthalene; this was mainly attributed to the amount of secondary mesopores in the SAPO-11 molecular sieves.

Pleurotus ferulae is an edible mushroom and has been used in Uygur medicine for a long time. In this study, we purified polysaccharides from P. ferulae (PFPS) and investigated its structural characteristics. We obtained a homogeneous PFPS with a molecular weight of around 1600 kDa and prominent characteristic polysaccharide groups, which mainly contained glucose (97%), followed by mannose and galactose (3%). Both 1H and 13C NMR spectra indicated that PFPS contained both α- and β-anomeric configurations. Atomic force microscopy and Congo red-staining data further suggested that PFPS belonged to a linear branched structure that existed in flexible single chains at low concentrations and could form aggregates such as a triple-helical structure at high concentrations. Moreover, PFPS promoted the maturation of dendritic cells through a TLR4 mediated signaling pathway, which is characterized by the increased expressions of CD40, CD86, IL-12 and TNF-α and the decreased endocytosis. The results suggest that PFPS has immunoregulatory activities.

As a unique 2D carbon crystal with a zero bandgap nature, superior electron mobility and high transparency, graphene was introduced into BiOBr–TiO2 (BT) composites as a nano-filler by a facile one-pot approach to obtain a novel BiOBr–TiO2–graphene (BTG) ternary photocatalyst. The material exhibits superior photocatalytic activity towards the photodegradation of Rhodamine B under visible light irradiation, and has an enhancement in photocatalytic rate of up to 2.83-fold higher than that of the BT catalyst at an optimum content of 0.75 wt% graphene in the composites. The homogeneous hybrid colloids of BiNO3, tetrabutyl titanate and graphene oxide were employed as the precursor, while GO was reduced into graphene with a simultaneous formation of tetragonal BiOBr and amorphous TiO2 in the solvothermal process. The highly dispersed 2D graphene in the composites will not only serve as the electron reservoir, but also act as a conductive network to improve the migration efficiency of electrons. Furthermore, the spacer effect of graphene will increase the surface BiOBr concentration and decrease the crystal size of BiOBr, as well as facilitate the formation of relatively uniform channel-like pores, which is beneficial for the photocatalytic performance. The photodegradation in the BiOBr–TiO2–graphene system was carried out dominantly by an indirect dye photosensitization process and the superoxide radical anions ˙O2− were considered as the main reactive species. This work provides an in-depth perspective for understanding the graphene-involved photocatalytic mechanism and stimulates the design of novel catalytic materials for the exploitation and utilization of solar energy.