Biomimetic gas sensor derived from disposable bamboo chopsticks for highly sensitive and selective detection of NH3

Tens of billions of pairs of waste disposable bamboo chopsticks (DBC) are produced every year, and it is extremely important to utilize this resource effectively. Inspired by the structural similarity between the dog turbinate and bamboo, DBC were successfully carbonized into carbon materials with a similar structure to that of dog turbinate at different temperatures. The carbon materials derived from DBC were used gas sensors for the first time and the effect of carbonization temperature on the structures, carbon yield and gas sensing performance was studied. By optimizing the carbonization temperature, the biomimetic sensor realized the detection of ammonia (NH3) with high sensitivity and selectivity, exhibited the high response (71.82 k%) to 500 ppm NH3 at room temperature, and had a theoretical detection limit of 0.12 ppm. Furthermore, the biomimetic sensor showed excellent immunity to formaldehyde, acetone, relative humidity (RH) and other interference factors, and its response to 95% RH was less than one thousandth of that to 500 ppm NH3. Compared with the fresh sensor, after 50 days the fluctuation of the sensor's response to NH3 was less than 4.2%, and it still had excellent recovery capability in 10 consecutive response-recovery cycles. What’s more, the biomimetic sensor has been successfully used to monitor the freshness of mutton in the actual environment. This study provides a reference for the development of low-cost and high-performance gas sensors and the effective utilization of biomass waste.