Structural features of HNb 3 O 8 nanosheets and their catalytic performance in toluene nitration

HNb 3 O 8 nanosheet aggregates ( e -HNb 3 O 8 ) were prepared by exfoliation and aggregation of layered HNb 3 O 8 , which was obtained by protonation of KNb 3 O 8 . Especially, in this research, KNb 3 O 8 was synthesized through a novel polymerized complex method (PC) from niobium oxalate. The as-prepared samples were characterized by SEM, HRTEM, XRD, LRS, NH 3 -TPD, and FT-IR methods. The toluene nitration was used to evaluate the acid catalytic performance of HNb 3 O 8 and e -HNb 3 O 8 samples. The catalytic activity in toluene nitration was related to the structure and acidity of the as-prepared samples. The results show that e -HNb 3 O 8 has a higher specific surface area, stronger acidity and better para -selectivity than the precursor HNb 3 O 8 .