A Unique, Porous C(3)N(4) Nanotube for Electrochemiluminescence with High Emission Intensity and Long-Term Stability: The Role of Calcination Atmosphere

Developing excellent strategies to optimize the electrochemiluminescence (ECL) performance of C(3)N(4) materials remains a challenge due to the electrode passivation, causing weak and unstable light emission. A strategy of controlling the calcination atmosphere was proposed to improve the ECL performance of C(3)N(4) nanotubes. Interestingly, we found that calcination atmosphere played a key role in specific surface area, pore-size and crystallinity of C(3)N(4) nanotubes. The C(3)N(4) nanotubes prepared in the Air atmosphere (C(3)N(4) NT-Air) possess a larger specific surface area, smaller pore-size and better crystallinity, which is crucial to improve ECL properties. Therefore, more C(3)N(4)(•−) excitons could be produced on C(3)N(4) NT-Air, reacting with the SO(4)(•−) during the electrochemical reaction, which can greatly increase the ECL signal. Furthermore, when C(3)N(4) nanotube/K(2)S(2)O(8) system is proposed as a sensing platform, it offers a high sensitivity, and good selectivity for the detection of Cu(2+), with a wide linear range of 0.25 nM~1000 nM and a low detection limit of 0.08 nM.