Tuning boron-carbon-nitride films

Materials Science Thin films formed from boron, carbon, and nitrogen (BCN films) can exhibit a wide range of optical and electronic properties if they can be made as phase-pure materials. Giusto et al. report on a simple solution-based route to hydrogenated BCN films. Gels formed with different melamine and boric acid ratios (1:1 and 2:1) were deposited on substrates and then heated in dry nitrogen to produce homogeneous, optically transparent films with optical bandgaps of 2.9 and 3.4 electron volts, respectively. The material derived from the 2:1 gel exhibited sp2 bonding and avoided segregation into graphene and hexagonal boron nitride. Addition of small amounts of benzoguanamine to the gels allowed for additional compositional and bandgap tuning. J. Am. Chem. Soc. 142 , 20883 (2020).