Petal-biotemplated synthesis of two-dimensional Co3O4 nanosheets as photocatalyst with enhanced photocatalytic activity

Abstract A biomorphic Co 3 O 4 nanosheet was fabricated by using China rose petal as biotemplate. Ultraviolet–visible diffuse reflectance spectroscopy, nitrogen adsorption, Fourier-transform infrared spectroscopy, thermogravimetric analysis–differential scanning calorimetric analysis, scanning electron microscopy, transmission electron microscopy and powder X-ray diffraction were utilized to characterize the samples. The results revealed that the synthesized Co 3 O 4 sample exhibited the special 2D nanosheet morphology with the thickness of around 100 nm similar to the original peal. The 2D nanosheet structure and multiple-porous feature of the sample not only increased its specific surface area and more active sites for photodegradation reaction, but also facilitated mass transfer, light scattering and harvesting as well as inhibition of the photogenerated carrier recombination. Moreover, compared with the commercial Co 3 O 4 , the as-prepared Co 3 O 4 nanosheet showed a superior photocatalytic activity due to its 2D multiple-porous nanosheet structure and high specific surface area (51.36 m 2  g −1 ).