Graphene-oxide dual-stabilized Mg

The practical applications of lightweight high-entropy alloys (HEAs) in catalysis and electrochemical sensors are hindered by inadequate chemical stability and catalytic activity. This study presents one groundbreaking synthesis strategy for fabricating Mg0.3AlVCuZn HEA nanoparticles by integrating histidine/serine-functionalized boron-doped graphene quantum dot (HSB-GQD). Mg2+, Al3+, V5+, Cu2+ and Zn2+ are coordinated with HSB-GQD to Me-HSB-GQD complex,followed by thermal annealing and controlled oxidative post-treatment. The resulting Mg0.3AlVCuZn shows single-phase octahedral morphology with a small size of about 50 nm and dual graphene-oxide shielding. Unique structure fully exposes active sites and enhances structural and chemical stability across acidic/alkaline media, interface electron transfer, and improves the affinity with polar electrolyte. The s-p-d orbital hybridization among Mg/Al (s, p) and V/Cu/Zn (s, d) induces electron redistribution to optimize adsorption energetics and catalytic specificity. Mg0.3AlVCuZn shows ultrahigh catalytic activity that is more than 2-fold that of Au nanoparticles. The electrochemical sensor with Mg0.3AlVCuZn exhibits a broad linear range (0.01–100 µM), ultra-low detection limit (0.0057 µM, S/N = 3), and robust selectivity and long-term stability for electrochemical detection of doxorubicin in human urine. This study also offers a generalizable platform for engineering lightweight HEAs with tailored stability and multifunctional efficacy, bridging advances in catalysis, sensing and energy storage.