Kaisheng Xia

Facile one-pot synthesis of magnetic nitrogen-doped porous carbon for high-performance bilirubin removal from BSA-rich solution

The development of high-performance adsorbents for efficient removal of bilirubin from albumin-rich solution is still a considerable challenge. In this study, a magnetic nitrogen-doped porous carbon (m-NpC) was facilely synthesized through a simple one-pot route using the biomass chitosan and the iron salt Fe(NO3)3·9H2O as precursors, and NaCl as template agent, respectively. Intriguingly, the resulting m-NpC material showed a hierarchically micro–meso–macroporous structure, high surface area (289 m2 g−1), large pore volume (0.33 cm3 g−1), and good magnetic response. In particular, the basic site-rich surface of m-NpC obtained as a result of nitrogen doping could compete effectively with albumin for bilirubin binding. As such, the m-NpC was used as a magnetically separable bilirubin adsorbent and showed superior adsorption properties for bilirubin removal from a bovine serum albumin (BSA)-rich solution. Under optimized conditions, the maximum adsorption capacity of m-NpC was up to 72.4 mg g−1, which is significantly higher than the value achieved by magnetic non-nitrogen doped porous carbon (24.7 mg g−1), but also superior to those of many previously reported adsorbents for BSA-boned bilirubin removal. Moreover, as evidenced by hemolysis assay, this material exhibited only a negligible hemolysis effect. These results suggest that the composite developed in this work can be used as a promising adsorbent in blood purification application to mitigate the risk of excess bilirubin.

Facile and scalable synthesis of hierarchically porous graphene architecture for hydrogen storage and high-rate supercapacitors

Porous graphene materials have been developed for many energy applications. However, a facile and scalable synthetic approach is still a challenge. Herein, we prepare graphene-based carbons with hierarchically porous structures via a simple steam activation of oxygen-functionalized graphene nanosheets. The as-prepared carbons show interconnected micro-meso-macroporous structures, high specific surface areas up to 1238xa0m2xa0g−1 and ultra-large pore volumes up to 4.28xa0cm3xa0g−1. The highest hydrogen storage on the carbon sorbents is found to be 1.47xa0wt% at 77xa0K and 1xa0bar. As electrode materials for supercapacitor, one of the carbons delivers a specific capacitance of 121xa0Fxa0g−1 at 0.5xa0Axa0g−1 with 85% retention at 20xa0Axa0g−1. The enhanced surface area, unique porous structure combined with the inherent properties of graphene are responsible for the excellent performances in hydrogen storage and high-rate supercapacitors.