One-pot green synthesis of bimetallic hollow palladium-platinum nanotubes for enhanced catalytic reduction of p-nitrophenol

Bimetallic alloy nanostructures have garnered much attention due to their unique performances in catalytic processes. However, decline in catalytic activity over the life span has been a protracted limitation, ascribed largely to the aggregation or dissociation of particles and still remains a challenge for manufacturing bimetallic nanostructures of sufficient stability. Herein, a surfactant- and solvent-free greener strategy is presented for the fabrication of bimetallic palladium-platinum (PdPt) nanotubes (NTs), deploying lipid tubules as template and ascorbic acid as a reducing agent; the ensuing NTs comprise crystalline tubal nanostructures of ∼12 μm length, ∼500 nm cross-sectional diameter, and ∼57 nm tube wall thickness. When used for the catalytic reduction of p-nitrophenol (PNP), the PdPt NTs delivered improved kinetic apparent rate constants (k_app) compared to Pt NTs (0.5 min⁻¹ vs. 0.2 min⁻¹). Moreover, the NTs demonstrated high stability when used over multiple catalytic cycles thus opening up new potential routes for the fabrication of alloy NTs using lipid tubules as templates.