Synthesis and Characterization of "Ravine-Like" BCN Compounds with High Capacitance

Borocarbonitride-Based Emerging Materials for Supercapacitor Applications: Recent Advances, Challenges, and Future Perspectives

Supercapacitors have emerged as a promising energy storage technology due to their high-power density, fast charging/discharging capabilities, and long cycle life. Moreover, innovative electrode materials are extensively explored to enhance the performance, mainly the energy density of supercapacitors. Among the two-dimensional (2D) supercapacitor electrodes, borocarbonitride (BCN) has sparked widespread curiosity owing to its exceptional tunable properties concerning the change in concentration of the constituent elements, along with an excellent alternative to graphene-based electrodes. BCN, an advanced nanomaterial, possesses excellent electrical conductivity, chemical stability, and a large specific surface area. These factors contribute to supercapacitors' overall performance and reliability, making them a viable option to address the energy crisis. This review provides a detailed survey of BCN, its structural, electronic, chemical, magnetic, and mechanical properties, advanced synthesis methods, factors affecting the charge storage mechanism, and recent advances in BCN-based supercapacitor electrodes. The review embarks on the scrupulous elaboration of ways to enhance the electrochemical properties of BCN through various innovative strategies followed by critical challenges and future perspectives. BCN, as an eminent electrode material, holds great potential to revolutionize the energy landscape and support the growing energy demands of the future.

Nanostructured Carbon-Doped BN for CO2 Capture Applications

Carbon-doped boron nitride (denoted by BN/C) was prepared through the pyrolysis at 1100 °C of a nanostructured mixture of an alkyl amine borane adduct and ammonia borane. The alkyl amine borane adduct acts as a soft template to obtain nanospheres. This bottom-up approach for the synthesis of nanostructured BN/C is relatively simple and compelling. It allows the structure obtained during the emulsion process to be kept. The final BN/C materials are microporous, with interconnected pores in the nanometer range (0.8 nm), a large specific surface area of up to 767 m2·g-1 and a pore volume of 0.32 cm3·g-1. The gas sorption studied with CO2 demonstrated an appealing uptake of 3.43 mmol·g-1 at 0 °C, a high CO2/N2 selectivity (21) and 99% recyclability after up to five adsorption-desorption cycles.

Methylboronic acid MIDA ester (ADM) as an effective additive in electrolyte to improve cathode electrolyte interlayer performance of LiNi0.8Co0.15Al0.05O2 electrode

We investigated the effectiveness of using methylboronic acid MIDA ester (ADM) as an additive in an electrolyte to enhance the overall electrochemical and material properties of an LNCAO (LiNi_0.8Co_0.15Al_0.05O₂) cathode. The cyclic stability of the cathode material measured at 40 °C (@ 0.2 C) showed an enhanced capacity of 144.28 mAh g^-1 (@ 100 cycles), a capacity retention of 80%, and a high coulombic efficiency (99.5%), in contrast to these same properties without the electrolyte additive (37.5 mAh g^-1, ~ 20%, and 90.4%), thus confirming the effectiveness of the additive. A Fourier transform infrared spectroscopy (FTIR) analysis distinctly showed that the ADM additive suppressed the EC-Li⁺ ion coordination (1197 cm^-1 and 728 cm^-1) in the electrolyte, thereby improving the cyclic performance of the LNCAO cathode. The cathode after 100 charge/discharge cycles revealed that the ADM-containing system exhibited better surface stability of the grains in the LNCAO cathode, whereas distinct cracks were observed in the system without the ADM in the electrolyte. A transmission electron microscopy (TEM) analysis revealed the presence of a thin, uniform and dense cathode electrolyte interface (CEI) film on the surface of LNCAO cathode. An operando synchrotron X-ray diffraction (XRD) test identified the high structural reversibility of the LNCAO cathode with a CEI layer formed by the ADM, which effectively maintained the structural stability of the layered material. The additive effectively inhibited the decomposition of electrolyte compositions, as confirmed by X-ray photoelectron spectroscopy (XPS).

Microporous Borocarbonitrides BxCyNz: Synthesis, Characterization, and Promises for CO2 Capture

Porous borocarbonitrides (denoted BCN) were prepared through pyrolysis of the polymer stemmed from dehydrocoupled ethane 1,2-diamineborane (BH₃NH₂CH₂CH₂NH₂BH₃, EDAB) in the presence of F-127. These materials contain interconnected pores in the nanometer range with a high specific surface area up to 511 m² · g^-1. Gas adsorption of CO₂ demonstrated an interesting uptake (3.23 mmol · g^-1 at 0 °C), a high CO₂/N₂ selectivity as well as a significant recyclability after several adsorption-desorption cycles. For comparison's sake, a synthesized non-porous BCN as well as a commercial BN sample were studied to investigate the role of porosity and carbon doping factors in CO₂ capture. The present work thus tends to demonstrate that the two-step synthesis of microporous BCN adsorbent materials from EDAB using a bottom-up approach (dehydrocoupling followed by pyrolysis at 1100 °C) is relatively simple and interesting.

TiO2 NPs/h-BN: Preparation and catalytic activities of a novel AP catalyst

The thermal decomposition performance of an oxidizer directly determines the thrust and specific impulse properties of the solid propellant. Hexagonal boron nitride (h-BN) has the characteristics of high catalytic activity and good stability, which can improve the heat release and decomposition temperature of the oxidant, and then improve the energy performance of the propellant. In this study, a novel hybrid material TiO₂ NPs/h-BN was successfully prepared by in situ growth, and it was found that when 5 wt.% TiO₂ NPs/h-BN was added, the initial decomposition temperature of ammonium perchlorate (AP) decreased by 67.6°C. Due to the addition of TiO₂, the gap between the h-BN layers as well as the specific surface increased, which optimized its thermocatalytic performance, and it also proposed a catalytic mechanism for the thermal decomposition process of AP.

Green Synthesis of Boron Carbonitride with High Capacitance

Boron carbonitrides (BCN) have attracted great interest in superhard or energy storage materials. In this work, thin BCN sheets were synthesized at 250 °C by a facile and green solvothermal method. The structure and morphology were characterized by X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Based on the results of electrochemical experiments, the thin BCN sheet exhibited excellent capacitance performance (343.1 F/g at a current density of 0.5 A/g) and cycling stability (90%), which showed high potential applications in supercapacitors.