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Title: Ti‐Modified Imogolite Nanotubes as Promising Photocatalyst 1D Nanostructures for H 2 Production
Abstract Imogolite nanotubes (INTs) are predicted as a unique 1D material with spatial separation of conduction and valence band edges but their large band gaps have inhibited their use as photocatalysts. The first step toward using these NTs in photocatalysis and exploiting the polarization‐promoted charge separation across their walls is to reduce their band gap. Here, the modification of double‐walled aluminogermanate INTs by incorporation of titanium into the NT walls is explored. The precursor ratiox= [Ti]/([Ge]+[Ti]) is modulated between 0 and 1. Structural and optical properties are determined at different scales and the photocatalytic performance is evaluated for H2production. Although the incorporation of Ti atoms into the structure remains limited, the optimal condition is found aroundx= 0.4 for which the resulting NTs reveal a remarkable hydrogen production of ≈1500 µmol g−1after 5 h for a noble metal‐free photocatalyst, a 65‐fold increase relative to a commercial TiO2‐P25. This is correlated to a lowering of the recombination rate of photogenerated charge carriers for the most active structures. These results confirm the theoretical predictions regarding the potential of modified INTs as photoactive nanoreactors and pave the way for investigating and exploiting their polarization properties for energy applications.  more » « less
Award ID(s):
2117896
PAR ID:
10537160
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Small Methods
Volume:
8
Issue:
8
ISSN:
2366-9608
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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