Mesoporous fibrous silicon nitride by catalytic nitridation of silicon

Publication date: Available online 10 April 2019Source: Progress in Natural Science: Materials InternationalAuthor(s): Tatevik Minasyan, Le Liu, Marina Aghayan, Miguel A. Rodriguez, Sofiya Aydinyan, Irina HussainovaAbstractThe catalytic effect of metal oxide/alumina whiskers (CeO2, Mn3O4, NiO, Co3O4, Fe2O3, Cr2O3/AW) was evaluated on their ability to drive the nitridation of silicon and to generate mesoporous fibrous silicon networks. Silicon powder with different particles size along with the catalyst was nitridized at 1300 °C for 5 h in nitrogen and nitrogen diluted with 10 vol% ammonia atmospheres. Nitridation degree of silicon up to 99% was recorded using 1.5 wt% CeO2 and Fe2O3 catalysts in nitrogen-ammonia atmosphere. The catalyzed samples contain submicronic silicon nitride fibres with a diameter of 400–500 nm and a length of up to few micrometers. The compressive strength of 46 ± 1 MPa was measured for silicon samples catalyzed with nickel oxide/alumina whiskers and nitridized in N2/10 vol%NH3 atmosphere. Porous silicon nitride networks were produced with 45–52% porosity, pore sizes in the range of 370–1200 nm and median pore in the range of 495–1655 nm.Graphical abstract
Source: Progress in Natural Science: Materials International - Category: Materials Science Source Type: research