A new 2D layered aluminophosphate vertical bar Hada vertical bar(6)[Al-6(PO4)(8)](H2O)(11) supported highly uniform Ag nanoparticles for 4-nitrophenol reduction

Aluminophosphate with vertical bar Hada vertical bar(6)[Al-6(PO4)(8)](H2O)(11) (denoted as ZHKU-1) of a new two-dimensional (2D) layer has been synthesized by adopting the template of alkylated memantine. The structure of ZHKU-1 was constructed from the alternate connection of AlO4 and triply bridged PO4 tetrahedra ([O=PO3](3-)) with a P/Al ratio of 4: 3. The inorganic layers are linked and separated by protonated amine molecules and H2O molecules through extensive H-bonds to give a supervoid of 19.6 angstrom, containing an AAAA-stacked sequence along the b axis. The open framework of ZHKU-1 has been adapted for encapsulating silver nanoparticles through photodeposition, forming the catalyst Ag@ZHKU-1. The HRTEM images reveal the highly uniform Ag clusters with visually observed sizes of 1.9 nm. Moreover, Ag@ZHKU-1 has shown an efficient conversion of 99.3% within 75 s for the catalytic reduction of 4-nitrophenol. This remarkable catalytic activity of Ag@ZHKU-1 can be attributed to the large exposed surface and confinement effect of the 2D aluminophosphate of ZHKU-1.