Erratum: Multiple-Stage Structure Transformation of Organic-Inorganic Hybrid Perovskite CH 3 NH 3 PbI 3 [Phys. Rev. X 6 , 031042 (2016)]

摘要

In our paper, we reported a previously unobserved Raman-like band centered at around 550 cm?1 [e.g., Figs. 2(a)and 3(a)] and found that it diminished after the material degraded.Our latest study has revealed that the assignment of the 550 cm?1 band as a Raman band was erroneous, and thisRaman-like peak was in fact the result of stray light of the unusually strong photoluminescence (PL) signal, peaked ataround 770 nm, in the pristine sample. The strongest band-edge PL intensity was on the order of e0.5–1.0T × 105 cps [e.g.,Figs. 2(b) and 3(d)] at the same or comparable power as the Raman measurements. Assuming a typical stray-lightsuppression ratio of 10?4 to 10?5 for a single grating spectrometer (an exact value is not available from the manufacturer ofthe instrument), the stray-light level would be comparable to that of the observed “Raman” peak typically on the order of1 cps. In our new study, this broad band was eliminated after adding an appropriate short-pass filter to block the band-edgePL signal. The broad band at around 1340 cm?1, as shown in Fig. 5(a), has the same origin as the 550 cm?1 band.The observed anticorrelation between the signals of around 100 cm?1 and 550 cm?1 was the result of structuredegradation that enhanced the Raman signal near 100 cm?1 and, in the meantime, reduced the PL signal near the perovskitebandgap at around 770 nm but appeared at 550 cm?1 as stray light. The wrong interpretation of 550 cm?1 does not affectthe primary conclusion, i.e., the multiple-stage structure transformation and the interpretation of other results. We regret thiserror and intend to write a paper to report the latest findings in detail in the near future.