Low-Power and High-Performance Trimethylamine Gas Sensor Based on n-n Heterojunction Microbelts of Perylene Diimide/CdS.

In this work, low-power and high-performance gas sensors toward trimethylamine (TMA) are presented for the food quality control in the Internet of Things. An amphiphilic perylene diimide derivative (1,6,7,12-tetra-chlorinated perylene- N-(2-hydroxyethyl)- N'-hexylamine-3,4,9,10-tetracarboxylic bisimide, TC-PDI) is synthesized and further employed to construct the organic microrods of TC-PDI and organic/inorganic microbelts of TC-PDI/CdS by a phase transfer method. Due to the formation of n-n heterojunctions, the TC-PDI/CdS microbelts exhibit higher conductivity than the TC-PDI microrods alone, which present an efficient gas sensing platform for TMA determination at room operating temperature with high reproducibility and selectivity. Remarkably, the limit of detection, stability, and selectivity of the TC-PDI/CdS gas sensor are significantly improved, which ascribes to the efficient charge separation of n-n heterojunctions. More importantly, the fabricated gas sensor provides potential application of "on-site" and "on-line" TMA identification in real systems and suggests an efficient way to develop new hybrid n-n heterojunctions for a low-power and high-performance gas sensor.