P‑Type Cross-Linked\nSilicon Nanocomposites\nfor Improving the Lithium-Ion Deinsertion from Anode Materials of\nLithium-Ion Batteries

Silicon has been an extremely popular anode active material\nowing\nto its rather high theoretical specific capacity; however, volume\ndistension and the generation of an unstable SEI film during the lithium\ninsertion and deinsertion process severely limit its commercial development.\nHerein, a type of P-type cross-linked Si semiconductor rich in hole\ncarrier nanocomposite (Si@SiC@PF) on the basis of B doping is synthesized\nvia a facile vacuum direct current arc combined along with a high-temperature\nsolid phase method. B doping can transform Si into a stable P-type\nsemiconductor with a large number of hole carriers so as to effectively\naccelerate electron conduction on the Si surface and improve the deinsertion\nefficiency of lithium ions. In addition, we also discover that B doping\nalso can optimize the distribution of SiC with a strong Si–C\nbond energy to allow it to aggregate on the surface of Si, resulting\nin the growth of the hierarchical structure, thus better exerting\nits buffering effect. Then, coating amorphous carbon through pyrolyzing\nphenolic resin (PF) can improve the conductivity of the composite\nmaterial while providing ample space for accommodating the volume\nexpansion of Si and forming a stabilized SEI film. As an anode active\nmaterial for lithium-ion batteries, the specific discharge capacity\nstill remains at 1272 mAh·g<sup>–1</sup> after 300 cycles.