Magnesium oxychloride cement (MOC) is gaining attention as a sustainable alternative to Portland cement. Its mechanical performance and water resistance may be enhanced by reinforcement with two-dimensional nanomaterials, such as graphene (G) and graphene oxide (GO). However, the ecotoxicological impact of these composites, determining their implementation, remains largely unexplored. This study evaluated the effects of G platelets with a surface area of 750 m2/g (G750) and GO, both as isolated particles and embedded within MOC, on a range of prokaryotic (, , and ) and eukaryotic (, , and ) model organisms. G750 and GO exhibited species-specific antibacterial activity, notably inhibiting growth and biofilm formation, while remained largely unaffected. The addition of G750 or GO did not enhance MOC's antibacterial effect, as MOC alone exhibited strong antimicrobial activity. Both G750 and GO were toxic to at concentrations of ≥0.05 g/L, with GO showing greater toxicity. Phytotoxic effects were observed in , particularly with the GO and MOC-G750 composites. Algal growth was unaffected by MOC-G750 but inhibited by MOC-GO after extended exposure. G750, GO, and MOC samples showed no genotoxic potential in vitro and in vivo; ROS production occurred without a significant change from the control. Overall, incorporating G750 and GO into MOC improved material properties without substantially increasing ecotoxicity, though species- and material-specific responses underscore the need for thorough environmental impact evaluation.

• Publikační typ
• časopisecké články MeSH

The synthesis of graphene materials is typically carried out by oxidizing graphite to graphite oxide followed by a reduction process. Numerous methods exist for both the oxidation and reduction steps, which causes unpredictable contamination from metallic impurities into the final material. These impurities are known to have considerable impact on the properties of graphene materials. We synthesized several reduced graphene oxides from extremely pure graphite using several popular oxidation and reduction methods and tracked the concentrations of metallic impurities at each stage of synthesis. We show that different combinations of oxidation and reduction introduce varying types as well as amounts of metallic elements into the graphene materials, and their origin can be traced to impurities within the chemical reagents used during synthesis. These metallic impurities are able to alter the graphene materials' electrochemical properties significantly and have wide-reaching implications on the potential applications of graphene materials.

• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH