Surfactant-free interfacial growth of graphdiyne hollow microspheres and the mechanistic origin of their SERS activity

As a two-dimensional carbon allotrope, graphdiyne possesses a direct band gap, excellent charge carrier mobility, and uniformly distributed pores. Here, a surfactant-free growth method is developed to efficiently synthesize graphdiyne hollow microspheres at liquid-liquid interfaces with a self-supporting structure, which avoids the influence of surfactants on product properties. We demonstrate that pristine graphdiyne hollow microspheres, without any additional functionalization, show a strong surface-enhanced Raman scattering effect with an enhancement factor of 3.7 x 107 and a detection limit of 1 x 10-12 M for rhodamine 6 G, which is approximately 1000 times that of graphene. Experimental measurements and first-principles density functional theory simulations confirm the hypothesis that the surface-enhanced Raman scattering activity can be attributed to an efficiency interfacial charge transfer within the graphdiyne-molecule system. The 2D carbon allotrope graphdiyne possesses a direct band gap, high charge carrier mobility, and uniformly distributed pores. Here, the authors report the surfactant-free growth of graphdiyne hollow microspheres and investigate the origin of their SERS activity.

Automated summary

In this study, a surfactant-free growth method was developed to efficiently synthesize graphdiyne hollow microspheres with a self-supporting structure. Pristine graphdiyne hollow microspheres were found to exhibit a strong surface-enhanced Raman scattering effect without any additional functionalization, which can be attributed to efficient interfacial charge transfer within the graphdiyne-molecule system.