Design of Ultra‐Microporous Carbons by Interpenetrating MF Prepolymer into PAAS Networks at Molecule Level for Enhanced Electrochemical Performance

Bacterial cellulose-derived micro/mesoporous carbon anode materials controlled by poly(methyl methacrylate) for fast sodium ion transport

An advanced nanostructure with rational micro/mesoporous distribution plays an important role in achieving high electrochemical performance in sodium ion batteries (SIBs), especially the energy storage efficiency in the low-potential region during the charging/discharging processes. Here we propose a method of polymer-blended bacterial cellulose (BC) matrix to tune the micro/mesopores of polymer-BC derived carbon under a mild carbonization temperature. The targeted pore structure and electrochemical performance are optimized by controlling the amount of methyl methacrylate monomers via free-radical polymerization, and carbonized temperature via pyrolysis treatment. The constructed carbon materials display a stable 3D fibrous network with a large specific area and abundant micro/mesopores formed during the pyrolysis of the polymer poly(methyl methacrylate) (PMMA). Taking advantage of the constructed pore structure, the optimized carbon anodes derived from BC/PMMA composites show an enhanced Na⁺ diffusion rate with a high capacity of 380.66 mA h g^-1 at 0.03 A g^-1. It is interesting that it possesses superior low-potential capacity, and retains 42% of the total capacity even at a high scan rate of 1 mV s^-1. The proposed method of polymer-blended on cellulose matrix provides an energy-efficient way to achieve high low-potential capacity under facile processing conditions for fast sodium ion transport in SIBs.

Realizing high-performance and low-cost lithium-ion capacitor by regulating kinetic matching between ternary nickel cobalt phosphate microspheres anode with ultralong-life and super-rate performance and watermelon peel biomass-derived carbon cathode

Lithium-ion capacitors (LICs) are emerging as one of the most advanced energy storage devices by combining the virtues of both supercapacitors (SCs) and lithium-ion batteries (LIBs). However, the kinetic and capacity mismatch between anode and cathode is the main obstacle to wide applications of LICs. Therefore, the effective strategy of constructing a high-performance LIC is to improve the rate and cycle performance of the anode and the specific capacity of the cathode. Herein, the nickel cobalt phosphate (NiCoP) microspheres anode is demonstrated with robust structural integrity, high electrical conductivity, and fast kinetic feature. Simultaneously, the watermelon-peel biomass-derived carbon (WPBC) cathode is demonstrated a sustainable synthesis strategy with high specific capacity. As expected, the NiCoP exhibits high specific capacities (567 mAh g^-1 at 0.1 A g^-1), superior rate performance (300 mAh g^-1 at 1A g^-1), and excellent cycle stability (58 mAh g^-1 at 5 A g^-1 after 15,000 cycles). The WPBC possesses a high specific surface area (SSA) of 3303.6 m² g^-1 and a high specific capacity of 226 mAh g^-1 at 0.1 A g^-1. Encouragingly, the NiCoP//WPBC-6 LIC device can deliver high energy density (ED) of 127.4 ± 3.3 and 67 ± 3.8Wh kg^-1 at power density (PD) of 190 and 18240 W kg^-1 (76.4% capacity retention after 7000 cycles), respectively.