MgAl hydrotalcite supported ultrafine PdNi bimetallic catalyst for the dehydrogenation of dodecahydro-N-ethylcarbazole N-ethylcarbazole

Liquid organic hydrogen storage is a promising way of storing hydrogen. The development of efficient and lowcost dehydrogenation catalysts is still required to advance the commercialization of N-ethylcarbazole/dodecahydro-N-ethylcarbazole (NEC/H12-NEC) hydrogen storage and transport system. In this paper, PdNi bimetallic catalyst (Pd3Ni1/LDHs) supported on MgAl hydrotalcite was prepared by NaBH4 and ultrasound-assisted stepwise reduction. Ultrasonic cavitation could excite the hydroxyl hydrogen of hydrotalcite in the form of hydrogen radicals to reduce PdCl42- to Pd nanoparticles (NPs), and also promoted the formation of PdNi alloys as well as the dispersion of NPs. In the Pd3Ni1/LDHs catalyst, the average particle size of NPs was 1.98 nm, suggesting an excellent dispersion of Pd, Ni, and PdNi NPs. The electronic effects of Ni and Pd significantly improved the catalytic efficiency of Pd3Ni1/LDHs in H12-NEC dehydrogenation, resulting in a hydrogen release rate of 98.4% after 6 hat 180 degrees C, surpassing that of Pd/LDHs. It can be considered that the dehydrogenation performance of Pd3Ni1/LDHs for H12-NEC is related to the alloy phase, electronic structure and NPs size.