Biomass is rich, renewable, sustainable, and green resources, thereby excellent raw material for the fabrication of carbon materials. The diversity in structure and morphology of biomass are relevant in obtaining carbon materials with different structures and performances. The inherent ordered porous structure of biomass also benefits the activation process to yield porous carbons with ultrahigh specific surface area and pore volume. Besides, obtained biomass‐derived carbons (BDCs) are hard carbon with porous morphology, stable structure, superior hardness/strength, and good cycling performances when used in electrochemical capacitors (ECs). The inherent N, S, P, and O elements in biomass yield naturally self‐doped N, S, P, and O BDCs with unique intrinsic structures. In this paper, the synthesis approaches and applications of BDCs in ECs are reviewed. It shows that BDCs electrochemical performances are highly determined by their pore structures, specific surface areas, heteroatoms doping, graphitization degree, defects, and morphologies. The electrochemical performances of BDCs can further be improved by compositing with other materials, such as graphene, carbon nanofibers/nanotubes, transition metal oxides or hydroxides, and conducting polymers. The future challenges and outlooks of BDCs are also provided.

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To realize future carbon neutrality, clean and sustainable electrochemical energy conversion and storage technologies are indispensable. Current devices include rechargeable batteries (e.g., Li-ion, Na-ion, and K-ion battery), fuel cells, and supercapacitors (SCs) that hold crucial positions in solving the current energy crisis and environmental pollution issues. [1][2][3][4] SCs and rechargeable batteries are the most popular electrochemical energy storage devices meeting future energy development demands. SCs usually possess high-power densities and long cycling lives but still suffer from low-energy densities. By comparison, rechargeable batteries have high-energy densities but still limited by lowpower densities, poor cycling stabilities, and short cyclic lives. Such tremendous differences in electrochemical properties between SCs and rechargeable batteries mainly originate from the differences in charge storage mechanisms. [5] According to the different charge storage mechanisms, SCs can be classified into electric double-layer capacitors (EDLCs), pseudocapacitors, and hybrid capacitors. [6,7] SCs made of carbon materials, such as carbon-based EDLCs, store electric charges at the electrode and electrolyte interface via physical adsorption/desorption of electrolyte ions. This process only involves surface reactions of ions without ion diffusion within the bulk electrode materials. [7][8][9] Pseudocapacitance often involves a Faradaic charge storage process by fast and highly reversible surface or near-surface redox reactions. Typically, pseudocapacitive electrode could be distinguished in underpotential deposition, redox reactions of transition metal oxides, and intercalation pseudocapacitance. [7] In most cases, functionalized porous carbons, such as oxygen-containing functional groups or heteroatomdoped carbon materials, have both EDL capacitance and pseudocapacitive storage mechanisms. Hybrid capacitors combine the advantages of EDLCs and pseudocapacitors, in which one electrode stores electric charge through battery-type faradaic process, while the other electrode stores electric charge based on capacitive mechanism. [10,11] Rechargeable batteries, such as Li-ion batteries (LIBs) and post-LIBs based on different charge carriers such as Na + and K + , store electric charges through intercalation, deintercalation, or adsorption of ions between the anode and cathode during charge/discharge processes. [1] For electrocatalysis, processes such as oxygen reduction reaction (ORR) in fuel cells and hydrogen evolution reaction (HER), as well as oxygen evolution reaction (OER) in water splitting, N 2 reduction reaction (NRR) and CO 2 reduction reaction (CO 2 RR), all often require high overpotentials and manifest sluggish kinetics in the absence of catalysts. The electrocatalytic processes usually take place according to three critical steps: 1) mass diffusion; 2) electron transfer; and 3) surface or interface reactions. [12] Generally, electrocatalytic ORR is a three-phase reaction and mainly includes two pathways:...

3DG/LiMn2O4 composites exhibit a high specific capacity and excellent rate performance.

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Exponential fertilization (EF) can feed seedlings with more nutrients than needed for growth and continuous lighting is expected to reduce the risk of loading at high application rate. In this study, red-seed tree (Ormosia hosiei Hemsley & E. H. Wilson) seedlings were raised by EF at a low rate of 160 mg nitrogen (N) plant-1 (conventional) (N-phosphorus [P]-potassium [K], 12-9-12) and a high rate of 600 mg N plant-1 (intensive), which was adapted from previous studies with large-pot-seedlings. Both fertilizer regimes were nested to either of two light spectra from high-pressure sodium (HPS) and light-emitting diode (LED) sources with three replicates for each combined treatment. Seedlings subjected to the conventional regime in the LED spectrum showed better growth and greater biomass accumulation with higher leaf N and P contents than other ones. In the conventional fertilizer regime, the LED spectrum also resulted in higher photosynthesis shown by more pigments and higher N synthesis than the HPS spectrum. The HPS spectrum strengthened P synthesis in the intensive regime. The antioxidative activity was stimulated by a high dose of EF, hence excessive toxicity was likely induced. We recommend using the normal rate of 160 mg N plant-1 for the culture of red-seed tree seedlings with LED lighting to promote seedling quality without causing excessive nutrient toxicity.

The nonuniform zinc nucleation process on the surface of zinc metal anodes is known to result in irreversible dendrite growth, which brings the risk of short circuit for the zinc‐ion hybrid supercapacitor (ZIHS). Herein, a conductive carbon−zinc composite anode with dense active sites is reported to achieve controllable dendrite growth. This unique modified anode in the ZIHS enables extremely low polarization (47 mV) in the symmetric battery test and delivers excellent application performance (capacity retention of 97.7% for 10 000 cycles). In addition, the changes in crystallographic orientation and morphological characteristics of the zinc electrode during deposition are observed by ex situ analysis. The improved zinc nucleation pattern of the modified anode verifies that the carbon additive can significantly facilitate isotropy in Zn deposition. Such a successful application of this economic and expandable modification strategy shows that carbon additives have significant potential in improving the stability of the anode.

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