PhD Thesis Development of sensors based on Conductive Polymers and Carbon Quantum Dots for

Topic description

PhD Context and Scientific Challenge:

Institute Mines Telecom Nord Europe has a large experience on the development and characterization of gas sensors (ammonia, hydrogen sulphide, formaldehyde, etc…) for outdoor/indoor/industrial air quality monitoring and biomedical applications.

Organophosphorus compounds constitute a family of chemicals widely used in agricultural, industrial, and military applications. Highly toxic with a potential impact on human health and the environment, they make the development of rapid, sensitive, and cost-effective detection technologies essential.

Chemiresistive sensors are a promising alternative due to their simple architecture, low power consumption, and potential integration into portable devices. IMT NE group is specialized in conducting polymers (CPs)-based chemiresistors. CPs exhibit some interesting properties, including tuneable conductivity, sensitivity to chemical interactions, and compatibility with low-temperature fabrication processes. However, CPs alone are not adapted for OPs sensing and their combination with organic and inorganic materials is necessary.

Recent researches have shown that carbon dots (CDs), a 0-dimensional carbon nanomaterial, improved gas sensing performances of (semi-)conductive materials for fluorescent sensors and chemiresistors. CDs have several advantages over inorganic semiconducting materials, such as low toxicity, low cost, ease of manufacture, and abundant active sites. More importantly, their functionalization (-COOH, -N, -S) could provide additional surface-active sites to capture OPs through the hydrogen bonds interactions and surface functional groups.

Combining CPs with CDs opens new opportunities to improve sensor sensitivity, selectivity, and stability through the unique electronic and surface properties of these nanomaterials.

Furthermore, the environmental challenges associated with the manufacturing of electronic devices now require the development of greener ink formulations and processing to reduce the use of hazardous solvents and minimise the environmental footprint of the fabricated sensors.

This PhD project is positioned within this framework and aims to develop a new generation of high-performance chemiresistive sensors based on hybrid CPs:CDs materials fabricated using environmentally friendly processing approaches.

Scientific Objectives:

The main objectives of this PhD project are:

• To develop innovative CPs:CDs hybrid materials for the chemiresistive detection of gases.

• To optimise sensor fabrication processes (from formulation to (post-)deposition) to obtain devices featuring high sensitivity, low detection limits, rapid and reproducible responses.

• To understand the interaction mechanisms between OPs and sensitive materials to improve sensing performance.

• To develop proof of concept and prototypes, and test OPs sensors in representative environments.

Methodology:

The PhD candidate will work on the design, formulation, and processing of sensitive materials for chemiresistive gas sensors, focusing on OPs.

The experimental work will include:

• the development of eco-friendly ink formulations compatible with available deposition techniques (e.g. dip-coating, spin-coating, Direct ink writing,… );

• rheological and physicochemical investigations of the formulated inks;

• morphological, structural, and electrical characterisation of the developed materials;

• the fabrication of sensors using various processing techniques and their characterization under specific conditions (humidity, gas concentration, temperature, etc.);

The PhD candidate will work within a multidisciplinary environment at the interface of materials science, chemistry, nanotechnology, and printed electronics.

Teaching opportunities from L2 to M2 levels will be also possible in the frame of the IMT Nord Europe courses.

Expected results:

The research will:

• optimising sensitivity and detection limits;

• improving selectivity against interfering species;

• ensuring fabrication reproducibility;

• reducing the overall environmental impact of the whole fabrication process.

The results will be published in leading international journals in the fields of materials science, sensors development, and environmental science.

Starting date

-10-01

Funding category

Public funding alone (i.e. government, region, European, international organization research grant)

Funding further details