We designed and synthesized a novel Cu2OTiO2/g-C3N4 ternary heterostructure nanohybrid, which is a universal and specific visible-light-responding photocatalyst for instantaneous discolorations of organic dyes. Employing this said nanohybrid, rhodamine B, methylene blue and methyl orange can be fully discolored within 3, 10 and 15 min in the presence of H2O2 under visible-light irradiation, respect...