Zirconium nitride as a highly efficient nitrogen source to synthesize the metal nitride clusterfullerenes

Metal nitride clusterfullerenes(NCFs)have significant applications in molecular electronics,biomedical imaging,and nonlinear optical devices due to their unique structures.However,their wide applications are limited by the production quantity.In this work,the yields of metal nitride clusterfullerenes M3N@C80(M=Y,Sc,Gd)were greatly enhanced by utilizing zirconium nitride(Zr N)as an efficient nitrogen source for the arc-discharge method.Compared with the traditional synthetic route using N2gas as nitrogen source,the Zr N inside graphite tube can be vaporized simultaneously with metal and graphite,and then afford the high concentration of nitrogen atoms in the arc region,which will promote the formation of metal nitride clusterfullerenes finally.The Zr N can promote the yields of Y3N@C80,Sc3N@C80and Gd3N@C80,revealing the universal applicability of Zr N as a highly efficient nitrogen source.Specifically,the yield of Sc3N@C80was greatly improved when adding Zr N,and it shows over double yield compared to traditional synthetic route using N2gas.In addition,Zr N can also enhance the yields of paramagnetic azametallofullerene M2@C79N due to the high concentration of nitrogen atoms in the arc region.This new method enhances the production quantity of metal nitride clusterfullerenes and azametallofullerenes,and it will greatly promote the research and application of these molecular carbon materials.

Nanoplasmonic zirconium nitride photocatalyst for direct overall water splitting

The ability of plasmonic nanostructures to efficiently harvest light energy and generate energetic hot carriers makes them promising materials for utilization in photocatalytic water spitting. Apart from the traditional Au and Ag based plasmonic photocatalysts, more recently the noble-metal-free alternative plasmonic materials have attracted ever-increasing interest. Here we report the first use of plasmonic zirconium nitride (ZrN) nanoparticles as a promising photocatalyst for water splitting. Highly crystalline ZrN nanoparticles with sizes dominating at 30-50 nm were synthesized that exhibit intense visible and near-infrared absorption due to localized surface plasmon resonance (LSPR). Without utilizing any noble metal cocatalysts such as Pt, the plasmonic ZrN nanoparticles alone showed stable photocatalytic activity for H_(2) evolution in aqueous solution with methanol as sacrificial electron donor. The addition of a cobalt oxide (CoO_(x)) cocatalyst can facilitate the separation of photogenerated charge carriers and further improve the photocatalytic activity. The optimized CoO_(x) modified ZrN photocatalyst was observed not only to activate the O_(2) evolution reaction with presence of electron acceptor, but also to drive overall water splitting for the simultaneous H_(2) and O_(2) evolution in the absence of any sacrificial agents.

Microstructure, Hardness and Corrosion Resistance of ZrN Films Prepared by Inductively Coupled Plasma Enhanced RF Magnetron Sputtering

ZrN fihns were deposited on Si（111） and M2 steel by inductively coupled plasma （ICP）-enhanced RF magnetron sputtering. The effect of ICP power on the microstructure, mechanical properties and corrosion resistance of ZrN films was investigated. When the ICP power is below 300 W, the ZrN films show a columnar structure. With the increase of ICP power, the texture coefficient （To） of the （111） plane, the nanohardness and elastic modulus of the films increase and reach the maximum at a power of 300 W. As the ICP Power exceeds 300 W, the films exhibit a ZrN and ZrNx mixed crystal structure without columnar grain while the nanohardness and elastic modulus of the films decrease. All the ZrN coated samples show a higher corrosion resistance than that of the bare M2 steel substrate in 3.5% NaCl electrolyte. The nanohardness and elastic modulus mostly depend on the crystalline structure and Tc of ZrN（111）.

Synthesis of ZrN-Si_3N_4 Composite by Carbothermal Reduction and Nitridation of Zircon

Zircon （ ≤44 μm） and carbon black （≤30μm） were used as starting materials and mixed for 24 h using anhydrous ethanol as medium with the mass ratio of 100：40, dried fully at 60 ℃ and then dry mixed for 10 h. Specimens with size of Ф20 mm × 5 mm were pressed under 60 MPa, then dried fully at 120 ℃ , put into a furnace with 1. 0 L ·min^-1 nitrogen gas and fired at 1 400, 1 450, 1 480 and 1 500℃ for 6, 9 and 12 h, respectively. The phase composition and microstructure of the specimens were studied by XRD and SEM, and the carbothermal reduction and nitridation reaction process was thermodynamically analyzed. The results show that using zircon and carbon black as starting materials, ZrN - Si3N4 composite is synthesized by carbothermal reduction and nitridation reaction in nitrogen atmosphere. The composites with different compositions are obtained by controlling the firing temperature and partial pressure of CO gas. The proper firing temperature and holding time to synthesize ZrN - Si3N4 composite are 1 500 ℃ for 12 h.