Nanoparticulate Conjugated Microporous Polymer with Post-Modified Benzils for Enhanced Pseudocapacitor Performance

Conjugated microporous polymer (CMP)-based energy-storage materials were developed for pseudocapacitors. Nanoparticulate CMP (N-CMP) with an average diameter of 41 +/- 4 nm was prepared through kinetic growth control in the Sonogashira coupling of 1,3,5-triethynylbenzene with 1,4-diiodobenzene. The N-CMP is rich in a diphenylacetylene moiety in its chemical structure. Through the FeCl3-catalyzed oxidation of diphenylacetylene moieties, N-CMP with benzil moieties (N-CMP-BZ) was prepared and showed enhanced electrochemical performance as an electrode material of pseudocapacitors, compared with CMP, CMP-BZ, and N-CMP. In model studies, the benzil was redox active and showed two-electron reduction behavior. The excellent electrochemical performance of N-CMP-BZ is attributable to the enhanced utilization of functional sites by a nanosize effect and the additional redox contribution of benzil moieties.