Host–Guest Hybrid Redox Materials Self‐Assembled from Polyoxometalates and Single‐Walled Carbon Nanotubes

Abstract

The development of next‐generation molecular‐electronic, electrocatalytic, and energy‐storage systems depends on the availability of robust materials in which molecular charge‐storage sites and conductive hosts are in intimate contact. It is shown here that electron transfer from single‐walled carbon nanotubes (SWNTs) to polyoxometalate (POM) clusters results in the spontaneous formation of host–guest POM@SWNT redox‐active hybrid materials. The SWNTs can conduct charge to and from the encapsulated guest molecules, allowing electrical access to >90% of the encapsulated redox species. Furthermore, the SWNT hosts provide a physical barrier, protecting the POMs from chemical degradation during charging/discharging and facilitating efficient electron transfer throughout the composite, even in electrolytes that usually destroy POMs.

Cerium Oxide Nanoparticles Inside Carbon Nanoreactors for Selective Allylic Oxidation of Cyclohexene

“…532 eV associated to hydroxyl groups (Figure S3d, SI). This suggests that GNF acts as an electron reservoir compensating for the loss of electrons in ceria, as observed previously for other metal compounds inside carbon nanotubes, 79,80 effectively restoring the Ce 4+ /Ce 3+ balance.…”

Top-down synthesis of polyoxometalate-like sub-nanometer molybdenum-oxo clusters as high-performance electrocatalysts

“…28,29 In addition, Newton and colleagues have demonstrated that internal integration of POMs into conductive carbon nanotubes leads to remarkable improvement and stabilization of their electrochemical performance. 30 Here, we propose an unprecedented top-down approach for the deposition of polyoxometalate-like metal oxo clusters on high-porosity carbon electrodes. The approach employs classical solution-stable Keggin polyoxomolybdates [H 3 PMo 12 O 40 ] (¼ PMo 12 ), which combine Brønsted-acidity, redox-activity and catalytic activity.…”

Molecular Vanadium Oxides for Energy Conversion and Energy Storage: Current Trends and Emerging Opportunities

“…As an alternative approach, Walsh, Newton, Khlobystov, and co‐workers recently demonstrated the embedding of POMs inside electroactive carbon nanotubes. This ground‐breaking concept could in future be used to design composite electrode materials where the POM is electrically “wired” to a carbon support and leaching is virtually impossible [106] …”