Functions of Phytic Acid in Fabricating Metal‐Free Carbocatalyst for Oxidative Coupling of Benzylamines †

Preparation of Nitrogen and Phosphorus Doped Porous Carbon from Watermelon Peel as Supercapacitor Electrode Material

The use of green and sustainable biomass-derived compounds to obtain excellent electrochemical properties is important to address growing environmental and energy issues. In this paper, cheap and abundant watermelon peel was used as a raw material to successfully synthesize nitrogen-phosphorus double-doped bio-based porous carbon by a one-step carbonization method and explore it as a renewable carbon source for low-cost energy storage devices. The supercapacitor electrode exhibited a high specific capacity of 135.2 F/g at a current density of 1 A/g in a three-electrode system. A variety of characterization methods and electrochemical tests indicate that porous carbon prepared by this simple method has great potential as electrode materials for supercapacitors.

Interactions between atomically dispersed copper and phosphorous species are key for the hydrochlorination of acetylene

Vinyl chloride, the monomer of polyvinyl chloride (PVC), is industrially synthesized via acetylene hydrochlorination. Thereby, easy to sublimate but toxic mercury chloride catalysts are widely used. It is imperative to find environmentally friendly non-mercury catalysts to promote the green production of PVC. Low-cost copper-based catalysts are promising candidates. In this study, phosphorus-doped Cu-based catalysts are prepared. It is shown that the type of phosphorus configuration and the distribution on the surface of the carrier can be adjusted by changing the calcination temperature. Among the different phosphorus species, the formed P-C bond plays a key role. The coordination structure formed by the interaction between P-C bonds and atomically dispersed Cu²⁺ species results in effective and stable active sites. Insights on how P-C bonds activate the substrate may provide ideas for the design and optimization of phosphorus-doped catalysts for acetylene hydrochlorination.

Construction of a Phytic Acid-Silica System in Wood for Highly Efficient Flame Retardancy and Smoke Suppression

The intrinsic flammability of wood restricts its application in various fields. In this study, we constructed a phytic acid (PA)-silica hybrid system in wood by a vacuum-pressure impregnation process to improve its flame retardancy and smoke suppression. The system was derived from a simple mixture of PA and silica sol. Fourier transform infrared spectroscopy (FTIR) indicated an incorporation of the PA molecules into the silica network. Thermogravimetric (TG) analysis showed that the system greatly enhanced the char yield of wood from 1.5% to 32.1% (in air) and the thermal degradation rates were decreased. The limiting oxygen index (LOI) of the PA/silica-nanosol-treated wood was 47.3%. Cone calorimetry test (CCT) was conducted, which revealed large reductions in the heat release rate and smoke production rate. The appearance of the second heat release peak was delayed, indicating the enhanced thermal stability of the char residue. The mechanism underlying flame retardancy was analyzed by field-emission scanning electron microscope coupled with energy-dispersive spectroscopy (SEM-EDS), FTIR, and TG-FTIR. The improved flame retardancy and smoke-suppression property of the wood are mainly attributed to the formation of an intact and coherent char residue with crosslinked structures, which can protect against the transfer of heat and mass (flammable gases, smoke) during burning. Moreover, the hybrid system did not significantly alter the mechanical properties of wood, such as compressive strength and hardness. This approach can be extended to fabricate other phosphorus and silicon materials for enhancing the fire safety of wood.