An inorganic-organic hybrid nanomaterial with a core-shell structure constructed by using Mn-BTC and Ag 5 [BW 12 O 40 ] for supercapacitors and photocatalytic dye degradation.

Creating inorganic-organic hybrids with polyoxometalates (POMs) and metal-organic frameworks (MOFs) as energy storage and dye-degradation materials remains challenging. Here, a new hybrid nanomaterial Mn-BTC@Ag 5 [BW 12 O 40 ] is synthesized by using Ag 5 [BW 12 O 40 ] and Mn 3 (BTC) 2 (H 2 O) 6 (Mn-BTC, BTC = 1,3,5-benzenetricarboxylic acid) through a plain grinding method. The structure and morphology characterization by scanning electron microscopy (SEM), powder X-ray diffraction (XRD), and transmission electron microscopy (TEM) shows that the synthetic products have core-shell construction. Due to its unique structure wherein the core is Mn-BTC and the shell is Ag 5 [BW 12 O 40 ], it exhibits excellent capacitance performance. In a three-electrode system where nickel foam is a collector, at a current density of 1 A g -1 , its specific capacitance is 198.09 F g -1 ; after 5000 cycles, the capacitance retention rate is 94.4%. When the power density is 503.1 W kg -1 , the symmetrical supercapacitor reveals a high energy density which is 10.9 W h kg -1 . At the same time, the capacitance retention is 92.9% after 5000 cycles which showed good cycle stability. The photocatalytic degradation efficiencies of rhodamine B (RhB), methyl orange (MO) and methylene blue (MB) dyes exceed 90% after 140 min, and the degradation results remained unchanged after five photocatalytic cycles. The photocatalytic degradation mechanism shows that ˙OH has a major effect. The results show that this research provides a fresh idea for the development of energy storage and dye photocatalytic degradation materials.