One-dimensional hollow FePt nanochains: applications in hydrolysis of NaBH ₄ and structural stability under Ga ⁺ ion irradiation

Abstract Pt-based one-dimensional hollow nanostructures are promising catalysts in fuel cells with excellent activity. Herein, one-dimensional hollow FePt nanochains were shown to be efficient nanocatalysts in the hydrolysis of NaBH ₄ . The characterization of composition, structure and morphology identifies an ultrathin shell (∼3 nm) with uniformly distributed Fe ₃₀ Pt ₇₀ constituents. The H ₂ generation rate of hollow Fe ₃₀ Pt ₇₀ nanochains achieves 16.9 l/(min · g) at room temperature, while the activation energy is as low as 17.6 kJ mol ⁻¹ based on the fitting over the whole reaction time span. After the catalysis of NaBH ₄ hydrolysis, the morphology and composition of hollow FePt nanochains remain unchanged. Furthermore, the structural stability of hollow FePt nanochains under Ga ⁺ ion irradiation is clarified. Theoretical simulation indicates that the stopping range of such a Fe ₃₀ Pt ₇₀ shell is 7.7 keV, which offers a prediction that structure evolves diversely under Ga ⁺ ions below and above such energy. The Ga ⁺ ion irradiation experiments show a consistent trend with the simulation, where Ga ⁺ ions with kinetic energy of 30 keV make the hollow architecture subside and sputter away, while Ga ⁺ ions with kinetic energy of 5 keV only etch the top and lead to an eggshell structure.