Cyclic Polyoxometalate Built by Different {Co₆SiW₉}/{B₃Co₈SiW₉} Units for Photothermal Conversion.

Area of Science:

• Inorganic Chemistry
• Materials Science
• Nanotechnology

Background:

• Polyoxometalates (POMs) are versatile inorganic clusters with tunable properties.
• Photothermal conversion materials are crucial for applications like cancer therapy and catalysis.
• Developing novel POMs with enhanced photothermal properties is an active research area.

Purpose of the Study:

• To synthesize a novel cyclic cobalt-added polyoxometalate.
• To investigate its photothermal conversion properties.
• To evaluate its stability for potential applications.

Main Methods:

• Hydrothermal synthesis guided by a lacunary directing strategy.
• Characterization of the synthesized polyoxometalate structure.
• Photothermal conversion efficiency measurements under 1064 nm laser irradiation.

Main Results:

• Successful synthesis of a novel cyclic Co-added polyoxometalate, Na8Cs18[{Co8(μ6-O)(μ2-OH)(μ3-OH)2(H2O)(BO(OH)2)(B2O3(OH)2)(B-α-SiW9O34)2}{Co6(μ3-OH)3(H2O)6(B-α-SiW9O34)}]2·42H2O (1).
• Compound 1 exhibits intense broad absorption in the 800-1700 nm region due to Co2+ centers.
• Achieved a photothermal conversion efficiency of 38.4% with superior cycling stability, raising temperature from 23.0 to 64.1 °C in 90 s under 1064 nm laser irradiation.

Conclusions:

• The novel cyclic Co-added polyoxometalate exhibits excellent photothermal conversion performance.
• The material demonstrates high stability, indicating its potential for photothermal applications.
• The synthetic strategy provides a pathway for designing functional polyoxometalates.