Self-Organized Mesostructured Hollow Carbon Nanoparticles via a Surfactant-Free Sequential Heterogeneous Nucleation Pathway

Mesostructured hollow carbon nanoparticles have widespread applications. A big challenge in materials science is surfactant-free synthesis of hollow carbon nanoparticles with tunable mesostructures. Herein we report a new surfactant-free sequential heterogeneous nucleation pathway to prepare mesostructured hollow carbon nanoparticles. This strategy relies on two polymerizable systems, i.e., resorcinol formaldehyde and tetraethyl orthosilicate, each of which undergoes homogeneous nucleation and particle growth. By controlling the polymerization kinetics of two systems when mixed together, sequential heterogeneous nucleation can be programmed, leading to monodispersed and mesostructured hollow carbon nanoparticles with large mesopores, controllable mesostructures (bi- and triple-layered), and rich morphologies (invaginated, intact, and endoinvaginated spheres). For the first time, it is demonstrated that the invaginated structure shows better hemocompatibility compared to the intact one. The pristine hollow carbon nanoparticles with large pore size and high pore volume show the high loading capacity of biomolecules and successfully deliver biomolecules into cells. Our strategy has paved the way for the designed synthesis of unprecedented carbon nanostructures with potential applications in drug/biomolecule delivery.