Graphite-like Carbon Nitride Nanotube for Electrochemiluminescence Featuring High Efficiency, High Stability, and Ultrasensitive Ion Detection Capability.

Herein, for the first time, we introduced a novel electrochemiluminescence (ECL) luminophore based on a one-dimensional g-C3N4 nanotube using K2S2O8 as the coreactant. The g-C3N4 nanotube/K2S2O8 couple displayed very satisfactory ECL performance, i.e., an ECL efficiency (ΦECL) of 437% (vs 100% for the Ru(bpy)32+/K2S2O8 reference) and excellent ECL stability (the relative standard deviation (RSD) = 0.78%). By contrast, ΦECL and RSD of the control g-C3N4 nanosheet/K2S2O8 couple were merely 196% and 45.34%, respectively. The mechanism study revealed that the g-C3N4 nanotube features a large surface area and much lower interfacial impedance in the porous microstructure, which are beneficial for accelerating the charge transfer rate and stabilizing charge/excitons for ECL. Moreover, using the g-C3N4 nanotube/K2S2O8 system as a sensing platform, excellent Cu2+ detection capability was also achieved. Our work thus triggers a promising g-C3N4 nanomaterial system toward ECL application.