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Subject of the postdoc

Colloidal quantum dots for near infrared emission

Financed post-doctoral position.
Published on 21 January 2022
Imaging in the infrared wavelength range has been essential in scientific, military and surveillance applications. Currently, it is a crucial enabler of new industries such as autonomous mobility, augmented reality and biometrics. In a variety of imaging sensors an IR illumination system is required, for example in LiDAR and Face ID applications based on Time-Of-Flight. Colloidal semiconductor quantum dots (QDs) combine several advantageous features to realize such near infrared (NIR) sources: their emission spectrum can be precisely adjusted with size and composition, their emission efficiency and photostability can be enhanced by growing a shell of a larger bandgap semiconductor on their surface (core/shell QDs), and they can be produced and processed using solution-based low-cost and scalable techniques.

The project will be realized in collaboration with an industrial partner at the SyMMES unit of the Interdisciplinary Research Institute of Grenoble (IRIG), part of CEA Grenoble. State-of-the-art equipment or realizing all tasks of the project are available within the lab and at the nano-characterization platform PFNC (MINATEC). The applicant will evolve in a multidisciplinary environment and interact with the chemists and physicists of IRIG, as well as with our industrial partner. 
Currently high-quality NIR-emitting QDs are based on the use of lead chalcogenides (PbS, PbSe). Due to its toxicity, the use of lead in consumer electronics devices is strongly limited and the development of Pb-free alternative QD materials is highly desirable. Amongst other possible candidates, III-V semiconductors such as InAs appear as the ideal candidates for achieving tunable and narrow emission in the 800-1500 nm range. Nonetheless the chemical synthesis of InAs QDs and their core/shell structure is challenging and novel approaches are required to push the performance of these QDs to the same level as that obtained with classic QDs (e.g., CdSe, InP). The candidate will develop synthesis methods for monodisperse InAs core QDs in a wide size range and for core/shell structures of high fluorescence quantum yield and photostability. The obtained QDs will be characterized by means of UV-vis-NIR and PL spectroscopy, XRD, TEM, EDX, and XPS. Their potential for integration into NIR-LEDs will be explored in collaboration with other partners.
Candidate’s profile
The candidate must hold a Ph.D. in chemistry or materials science or physics and have a strong background in the synthesis of nanoparticles. Knowledge and experience in chemical synthesis under inert conditions (glove box, Schlenk technique) and in several of the above-mentioned characterization techniques will be required. 

send a CV, the contact details of two references and a letter of motivation to Peter Reiss.

Starting date
As soon as possible.