Fig. 2

Evolution of BiOCl MSLs growth and different reaction times properties characterization. a TEM images and b XRD patterns measured at different reaction times during the BiOCl MSLs growth process (scale bar: 500 nm). In (b), red lines represent the benchmark data from the JCPDS card (#06-0249, BiOCl in space group P4/nmm). c Band gap values (in black) and existence percentage (in blue) of MSLs as the function of reaction time. Band gaps are deduced from absorption spectra (Supplementary Fig. 13). MSL percentage is evaluated based on the coverage of the spiral nanosheet region on the TEM images. The error bar represents the variation range of the data from multiple times of measurements. d Time-resolved photoluminescence spectra of BiOCl bulk (in black), BiOCl MSL nanosheets measured at the reaction time of 30 min (in red), 120 min (in blue), respectively. The measurements were taken via time-correlated single-photon counting (monitored at 455 nm) with an excitation wavelength of 365 nm. The average carrier lifetimes inferred from the emission decay (see main text) are indicated