Pores on TiO2 nanosheets with exposed high active facets

•Anatase TiO2 nanosheets with high active facets {001} exposed have been fabricated.•These nanosheets can stay stable in atmosphere for long time.•Pores on nanosheets are caused by electron irradiation in observation.•Storage of the nanosheets is not a problem in application.

Anatase titanium dioxide nanosheets with exposed highly active {001} facets are very important for photo-catalysis because of their superior catalytic properties. However, pores are always found to be present on the nanosheets in transmission electron microscopy (TEM) observation, which would degrade their catalytic performance. The origin of the pores is as yet unclear. In this study we use TEM to investigate the origin and nature of the pores. It is found that, instead of chemicals used in the preparation process, it is irradiation damage from the electron beam results in the pores.