Preparation of trace heteroatom self-doped sensing materials with fast recovery properties derived from egg custard

For the first time, egg custard, typically considered a potential carbon material, was transformed into gas-sensing materials using an eco-friendly, inexpensive, and straightforward carbonization process. Detailed examination proved that the carbonized egg custard at 600 °C exhibited a hollow configuration with nanoscale pores, greatly enhancing the surface area for gas adsorption. Furthermore, heteroatoms self-doped biomass-derived carbon materials can offer a plentiful supply of reactive sites and modify the material's shape to facilitate gas adsorption. The carbonized egg custard sensor showed good selectivity, repeatability, and a moderate response-recovery cycle to NH 3 . Density functional theory calculations further confirmed that doping with trace heteroatoms enhances the adsorption of O 2 and NH 3 molecules. This work provides a novel and sustainable approach for converting egg custard into biomass-derived carbon materials with promising gas-sensing applications.