Revealing the synergistic effect of capillary force and electrostatic attraction for D-SERS sensitivity.

To overcome the relative weak stability and reproducibility of solid substrates and the long no-signal duration before the short signal-on period of dynamic SERS (D-SERS) strategies, we introduced an electrostatic attraction between the molecule and the D-SERS substrate. The synergistic effect between capillary force and electrostatic attraction during D-SERS measurements improves the SERS sensitivity by 2-3 orders of magnitude compared to that for a solid SERS substrate prepared via liquid-liquid interface self-assembly.