Tunable bandgap in hybrid perovskite CH3NH3Pb(Br3−yXy) single crystals and photodetector applications

Abstract

We report the synthesis of CH3NH3Pb(Br3−yXy) (X=Cl and I) single crystals via a stepwise temperature control approach. High-quality CH3NH3Pb(Br3−yXy) crystals with a tunable bandgap from 1.92eV to 2.53eV have been prepared successfully in this way. And further experiments revealed the influence of halogen content and preparation temperature on the structural and optical properties of these crystals. It is observed that chlorine can lower the critical nucleation energy, which results in crystallizing at lower temperature with the chlorine content increasing, while the nucleation energy increases slowly with increasing iodine content. Moreover, in contrast to Frank–van der Merwe growth with low heating rate, high heating rate leads to a mass of small size single crystals and Stranski-Krastanov growth. The single crystals with tunable band gap and impressive characteristics enable us to fabricate high performance photodetectors for different wavelengths.

Revealing the Chemistry between Band Gap and Binding Energy for Lead‐/Tin‐Based Trihalide Perovskite Solar Cell Semiconductors

“…The band gap for the CH 3 NH 3 PbY 3 series is tunable in the 1.50–3.10 eV range . This range has been routinely determined experimentally with a range of very common measurement techniques by diverse research groups, which have justified urgency in publication in many high‐impact journals.…”

“…[138] The band gap for the CH 3 NH 3 PbY 3 series is tunable in the 1.50-3.10 eV range. [86,[106][107][108][109] This range has been routinely determined experimentally with ar ange of very common measurementt echniques by diverser esearch groups, which have justifiedu rgency in publication in many high-impactj ournals. Interestingly,t he aforementioned band gapr ange coversa substantial part of the visible range of the electromagnetic spectrum( 1.59 (red)-3.26 eV (violet)) ande xtends up to the near-IRregion (0.90-1.58 eV).…”

Visualizing Phase Segregation in Mixed‐Halide Perovskite Single Crystals

“…Notably, adifferent I/Br ratio in the final composition can be achieved with elevated temperatures (Figure S8 c) owing to the different nucleation energies of Br-a nd I-based perovskites. [14] Atomic force microscopy (AFM;F igure S9), SEM ( [12] suggesting ah igh-quality single-crystal material.…”

Perovskite/Silicon Tandem Solar Cells: From Detailed Balance Limit Calculations to Photon Management

“…Recently, the energy conversion efficiency of the perovskite/silicon tandem solar cell has reached to 28% [38], which is reported by Oxford PV; however, detailed on the used solar cell structure has not been revealed yet. The bandgap of the perovskite material system can be controlled over a wide range [58][59][60][61]. In this study, we will use CH 3 NH 3 PbI 3 , the best-studied material out of the group of perovskites.…”