The photos of the prepared MPCMs samples with NaBF4 (MPCM-45-F4) and KF as fluorine source, respectively, before and after they were heated at 50 °C are showed in Fig. 1. The figure revealed that the leakage of MPCM-45-F4 was negligible during the heating process. However, the large wet area on the filter paper below the MPCM with KF as fluorine source indicated the sample leaked seriously. It should be noted that when KF was used, all the obtained samples exhibited severe leakage, even the
