One-Pot Template-Free Hydrothermal Synthesis of Monoclinic BiVO₄ Hollow Microspheres and Their Enhanced Visible-Light Photocatalytic Activity

Table 1

Experimental conditions for preparation of the samples and their physical properties.

No.	Urea content	Phase^a	Bandgap (eV)	Crystalline size (nm)	SBET (m^2/g)	Relative crystallinity^b
A	0	M	2.24	31.1	2.85	1.00
B	3	M	2.22	45.2	1.64	1.48
C	6	M	2.21	50.6	1.20	1.80
D	9	M	2.20	62.5	1.05	2.13

^aM denote monoclinic.
^bRelative monoclinic crystallinity: the relative intensity of the diffraction peak from the monoclinic (121) plane (reference = the sample A prepared in pure water).