Phosphorus-Doped Carbon Nitride Solid: Enhanced Electrical Conductivity and Photocurrent Generation

As a new kind of polymeric semiconductors, graphitic carbon nitride (g-C(3)N(4)) and its incompletely condensed precursors are stable up to 550 degrees C in air and have shown promising photovoltaic applications. However, for practical applications, their efficiency, limited e.g. by band gap absorption, needs further improvement. Here we report a "structural doping" strategy, in which phosphorus heteroatoms were doped into g-C(3)N(4) via carbon sites by polycondensation of the mixture of the carbon nitride precursors and phosphorus source (specifically from 1-butyl-3-methylimidazolium hexafluorophosphate ionic liquid). Most of the structural features of g-C(3)N(4) were well retained after doping, but…