Research Work on a 2D material from Prof. Katiyar’s group was accepted in Nano Letters (a journal with Impact factor of over 13)

07/24/ 2014


Surface Energy Engineering for Tunable Wettability through Controlled Synthesis of MoS2


Gaur, Anand; Sahoo, Satyaprakash; Ahmadi, Majid; Dash, Saroj; Guinel, Maxime; Katiyar, Ram



MoS2 is one of the important members of transition metal dichalogenides which is emerging as a potential 2D atomically thin layered material for low power electronics and opto-electronics applications. However, for MoS2 a critical fundamental question of significant importance is how the surface energy and hence the wettability is altered in nanoscale in particular, the role of crystal quality in low dimensions. The present work reports synthesis of large area MoS2 films on insulating substrates with different surface morphology via vapor phase deposition by varying the growth temperatures. The crystallinity of the samples is examined by transmission electron microscopy and Raman spectroscopy. From contact angle measurements, it has been possible to correlate the wettability with crystallinity at nanoscale. The specific surface energy for few layers thick MoS2 is estimated to be around 46.5 mJ/m2. The results shed light on the MoS2-water interaction which is significant for developing important devices based on MoS2 coated surfaces for micro-fluidic applications.