▎ 摘　　要

Underwater sound absorption materials with broadband and resistance to high pressure are crucial for noise control in the ocean. Herein a new method is presented to synergistically improve material's resistance to high pressure with broadband by hybridizing carbon nanotubes (CNTs) with graphene nanoplatelets (GNPs) in polydimethylsiloxane (PDMS) matrix. The micro-structure shows the geometrical synergy between the nanoplatelets (GNPs) and nanotubes (MWCNT-COOH). Besides, GNPs also form junctions with air micro-voids. The underwater acoustic tests reveal that, compared with equivalent nanocomposites containing only CNTs or GNPs, the hybridized materials show significantly better sound absorption performance with a high hydrostatic pressure increased from 0.4 MPa to 1.0 MPa at the frequency range of 1500 Hz to 7000 Hz. Therefore, the hybridization of one-dimensional (1D) and two-dimensional (2D) nano-carbon materials provides a new route for increasing the underwater sound absorption performance at high hydrostatic pressure.