Innovative strategy to recognize the diabetic state of people: metal oxide nanorods as ultrasensitive exhaled gas sensor

The project aims to develop an ultrasensitive gas sensor based on p-n heterostructured
nanorods toward enhance gas sensitivity by a larger modulation in current through the
heterojunction barrier for acetone detection; theoretical explanation of sensing mechanism by
first-principals calculation and assembling working prototype.
The main tasks of the project
1. Optimization of the gas sensing material, enhance its selectivity for acetone
2. Gas sensitivity test with exhaled gas
3. Construct a working prototype and calibrate it with real glucose concentration and beta-
hydroxybutyrate in blood and acetone in exhaled breath
4. Develop a mobile app for effective body mass control and diabetes prophylactics

Abstract
In recent years, the development of gas monitoring devices/sensors are critical for
environmental protection and for humans promptly. Due to their good characteristics as fast
response, low cost, and small size gas sensors have become more prevalent in different fields
from healthcare industries to food processing. In breath sensing, metal oxide semiconductor
(MOS) sensors are commonly utilized. MOS sensors are one of the finest alternatives for breath
analysis because of its:
• compact size,
• ease of operation,
• low cost,
• and minimal maintenance
However, conventional gas sensors with a single metal oxide layer, detect a shift in bulk
resistance in response to gas contact, resulting in limited gas sensitivity and selectivity. For
increasing gas sensitivity and selectivity, forming a p-n junction with MOS-based p-type and n-
type electrodes is the best option. This research purpose to investigate gas sensor based on p-n
heterostructures of MOS (TiO/CuO) with nanoscale architecture which is ultrasensitive for
VOCs and work at low temperature (room temperature).