Rational design of carbon nitride photocatalysts by identification of cyanamide defects as catalytically relevant sites

The heptazine-based polymer melon (also known as graphitic carbon nitride, g-C3N4) is a promising photocatalyst for hydrogen evolution. Nonetheless, attempts to improve its inherently low activity are rarely based on rational approaches because of a lack of fundamental understanding of its mechanistic operation. Here we employ molecular heptazine-based model catalysts to identify the cyanamide moiety as a photocatalytically relevant 'defect'. We exploit this knowledge for the rational design of a carbon nitride polymer populated with cyanamide groups, yielding a material with 12 and 16 times the hydrogen evolution rate and apparent quantum efficiency (400 nm), respectively, compared with the unmodified melon.…

• DF
  Deutsche Forschungsgemeinschaft

  Awards: SE1417/5-1, LO1801/1-1
• FD
  Fundação de Amparo à Pesquisa do Estado de São Paulo

  Award: 2014/
• M
  Max-Planck-Gesellschaft