Black TiO2 nanotubes formed by high energy proton implantation show noble-metal-co-catalyst free photocatalytic H2-evolution

TL;DR

This study demonstrates that high-energy proton implantation creates intrinsic co-catalytic centers on TiO2 nanotubes, enabling efficient, noble-metal-free photocatalytic hydrogen evolution through defect engineering and electronic property modification.

Contribution

The paper introduces a novel method of using high-energy proton implantation to activate TiO2 nanotubes for photocatalytic H2 production without noble metal co-catalysts.

Findings

Proton implantation induces specific defects and modifies electronic properties.

A synergistic effect enhances photocatalytic activity in nanotubes.

Intrinsic co-catalytic centers enable noble-metal-free H2 evolution.

Abstract

We apply high-energy proton ion-implantation to modify TiO2 nanotubes selectively at their tops. In the proton-implanted region we observe the creation of intrinsic co-catalytic centers for photocatalytic H2-evolution. We find proton implantation to induce specific defects and a characteristic modification of the electronic properties not only in nanotubes but also on anatase single crystal (001) surfaces. Nevertheless, for TiO2 nanotubes a strong synergetic effect between implanted region (catalyst) and implant-free tube segment (absorber) can be obtained.