Snowball flower-like g-C3N4/ZnFe2O4 mesoporous hollow microspheres with enhanced triethylamine sensing properties

Herein, the snowball flower-like g-C3N4/ZnFe2O4 mesoporous hollow microspheres, in which two-dimensional (2D) g-C3N4 nanolayers were loaded onto the surface of ZnFe2O4 hollow microspheres, were constructed by a simple solid phase reaction. The effect of the g-C3N4 concentration on the structure, morphology and gas-sensing performance of the g-C3N4/ZnFe2O4 composites had been explored. On the basis of gas sensitivity test results, the composites owned lower working temperature (160 degrees C) and better selectivity toward TEA in comparison with pure ZnFe2O4. Notably, the sensor based on the g-C3N4/ZnFe2O4-15 hollow microspheres (adding 15 ml of g-C3N4 aqueous solution) exhibited outstanding sensing properties, including superior response (18.3) toward 100 ppm TEA at optimum work temperature of 160 degrees C, speedy response-recovery time (33, 30 s) and outstanding stability. And the sensor maintained high response of 4.3 to low concentration TEA (5 ppm). The improved gas-sensing performance of the composites could be attributed to the porous ZnFe2O4 hollow microspheres loaded by 2D g-C3N4 nanolayers with large specific surface area and the heterostructure formed between them. Hence, a potential application of the g-C3N4/ZnFe2O4 microspheres might be achieved in detecting TEA at a low optimum work temperature.