State-of-the-art advances in the structural diversities and catalytic applications of polyoxoniobate-based materials

Polyoxoniobates (PONbs), a remarkable category of metal-oxo cluster materials, have attracted significant attention, owing to their structural diversity and high nucleophilicity. Because of their special electronic structures, adjustable energy bands, and high stabilities, PONb-based functional materials can be environmentally friendly catalyst candidates. Herein, we systematically summarise typical PONbs reported in the past several decades, which can be generally classified into five categories: isopolyoxoniobates, heteropolyoxoniobates, transition-metal-containing PONbs, rare-earth-containing PONbs, and transition-metal-rare-earth-containing PONbs. Their compositions, structural diversities, and catalytic properties and applications have been comprehensively discussed. This review provides some instructive guidance for the further discovery and development of efficient and robust PONb-based functional materials in the future.