Fig. 1(A–D) shows the P-Ag@AgCl synthesized at pH value of 2.1, 7.8,9.0 and 11.0,and the productsare noted as P–Ag@AgCl–PVP–2.1 to 11.0. Interestingly, these nanopar- ticles exhibit clearly different shapes and compositions with the pH value increasing.