Synthesis, Crystal Structure, Electronic Structure, and Catalytic Properties of Ni3GaSb

Single crystalline titled phase is synthesized by conventional high-temperature solid-state synthesis. Crystal structure of Ni3GaSb is re-investigated by single-crystal X-ray diffraction and energy dispersive X-ray analysis. The compound crystallizes in P6(3)/mmc space group, the structure can be described as an intermediate of NiSb and Ni2In structures, similar to Ni3GaAs. Electronic structure of the compound is investigated by first-principles electronic structure calculations on the ordered model of Ni3GaSb. Stability and bond analysis was done by COHP calculations. Hetero-atomic Ni-Sb and Ni-Ga interactions play a major role towards to stability of the compound, these interactions are also responsible to modify the electronic structure of the titled compound. It was tested for catalytic activity and selectivity for acetylene hydrogenation reaction. Ni3GaSb was found to be a selective catalyst with 95.53 % C2H2 conversion giving 60 % selectivity towards C2H4 at 550 degrees C.