Bandgap tunable Cs_x(CH₃NH₃)_1−xPbI₃perovskite nanowires by aqueous solution synthesis for optoelectronic devices

Abstract

To date, all the lead halide based full-inorganic or organic-inorganic hybrid perovskites have been synthesized from organic solvent, such as N,N-dimethylformamide (DMF) or dimethyl sulfoxide (DMSO), by a solution method. Herein, water has been utilized as a 'green' solvent to develop an efficient synthetic route to grow various kinds of lead halide perovskite nanowires (NWs). By controlling the proportion of the hybrid cations, Cs(CHNH)PbI perovskite NWs were successfully synthesized. Every Cs(CHNH)PbI perovskite NW demonstrated single crystal characteristics with uniform stoichiometric element distribution. Because of the controllable cation composition, the NW bandgaps could be finely tuned from 1.5 to 1.7 eV. Transient photoluminescence spectra showed superior NW quality when compared with those of the conventional DMF-based NWs. Based on the abovementioned high quality single Cs(CHNH)PbI perovskite NW, a reliable single-NW photodetector was fabricated to investigate the optoelectronic application. It demonstrated a responsivity of 23 A/W, exceeding most of the reported values in the perovskite nanowire photoconductive detectors, and the shot-noise normalized detectivity was 2.5 × 10 Jones comparable to the parameters of the commercial silicon-based nanowires. The green and robust synthesis method, finely tunable NW bandgaps, and superior optoelectronic properties are expected to open a new door for the development of perovskite optoelectronic devices.

Hybrid Organic–Inorganic Perovskite Photodetectors

“…To enlarge or tune the device response range, one possible strategy is to change its bandgap. Because the absorption edges of MAPbCl 3 , MAPbBr 3 , and MAPbI 3 are located in the UV, visible, and NIR ranges, respectively, a sequential tuning of the perovskite bandgap over a wide spectrum range is viable by varying the composition . For instance, Liu and co‐workers succeeded in growing single crystals of MAPb(Br x I 1− x ) 3 with varying x in full range from 0 to 1, which enabled bandgap tuning from 1.53 to 2.24 eV, corresponding to absorption spectrum edge shifted from green to red .…”

Low‐dimensional metal halide perovskites and related optoelectronic applications

“…In 2014, Horvath did the pioneering work of perovskite nanowire‐based detectors (Figure A) . Although the responsibility of this detector is 5 mA W −1 , 4 orders of magnitude smaller than that of state‐of‐art detectors made from monolayer graphene, the response times (rise and decay times) were within 500 μs, ~10 4 faster than that of graphene‐based detectors (Figure B) .…”

“…In 2014, Horvath did the pioneering work of perovskite nanowire-based detectors ( Figure 15A). [168][169][170][208][209][210][211][212] Although the responsibility of this detector is 5 mA W −1 , 4 orders of magnitude smaller than that of state-of-art F I G U R E 1 2 A, Schematic of a perovskite nanowire on SiO 2 substrate pumped by the laser excitation. B, Emission spectra of MAPbI 3 nanowires at the intensities around the lasing threshold.…”

Recent Advances in Halide Perovskite Photodetectors Based on Different Dimensional Materials

“…The effective method resulted in reduced trap density, extended life time, and increased carrier mobility. Interestingly, Dong et al also explored water as a “green” solvent for the synthesis instead of organic solvents, such as DMF or dimethyl sulfoxide. Cs x (MA) 1− x PbI 3 PNWs were successfully synthesized with tunable bandgap (1.5–1.7 eV) by simply controlling the cation composition.…”