Graphite　carbon　nitride　nanosheets　(g-C(3)N(4)NSs)　are　the　promising　metal-free　polymer-like　semiconductor　nanomaterials,　which　exhibit　excellent　electrochemiluminescence　(ECL)　behavior.　The　g-C(3)N(4)NSs　modified　the　glass　carbon　electrode　showed　the　obvious　ECL　response　using　10　mM　S2O82-　as　the　co-reactant　at　the　scan　rate　of　0.1　V/s.　The　presence　of　Cu2+　would　quench　ECL　emission　due　to　the　photo　induced　electron　transfer　(PET).　Pyrophosphate　anion　(PPi),　an　important　anion　in　several　bioenergetics　and　metabolic　processes,　can　chelate　with　Cu2+　with　a　strong　affinity.　The　introduction　of　PPi　could　release　Cu2+　from　Cu2+-g-C(3)N(4)NSs　system,　resulting　in　the　ECL　recovery.　The　dosage　of　Cu2+　and　the　ECL　recover　time　were　further　investigated.　Under　the　optimized　condition　PPi　can　be　detected　in　the　range　of　2.0-800　nM　with　the　detection　limit　of　75　pM　based　on　3o/slope.　This　ECL　sensor　also　possessed　good　selectivity　to　PPi,　and　has　been　used　to　detect　PPi　in　the　synovial　fluid.　(C)　2016　Elsevier　B.V.　All　rights　reserved.