Role of Heterocyclic Organic Compounds on the Optoelectronic Properties of Halide Perovskite Single Crystals

Single crystals (SCs) of metal halide perovskites (MHPs) are known to possess superior properties. However, the surface of the SCs possesses a higher defect density, which can deteriorate the optoelectronic properties of SCs. Herein, we have engineered the growth of methylammonium lead tribromide SCs using (R)-3-aminopiperidine dihydrochloride (API). The modified crystals also showed improved photoresponse validated by the increased photocurrent. The modified crystal showed a highest photoresistivity of 0.47 mA/W and a detectivity of 3.7 x 1011 Jones at an applied bias of 2 V. On the other hand, the control crystal showed a resistivity of 0.32 mA/W and a detectivity of 1.0 x 1011 Jones. This shows that the API additive improves the charge collection efficiency and reduces the recombination. The charge accumulation and ion migration were further studied using electrochemical impedance spectroscopy and capacitance-frequency measurement. Thus, this study presents systematic investigation of the electrical response of additive-modified crystals.

Automated summary

This study improves the optoelectronic properties of methylammonium lead tribromide single crystals by modifying their growth conditions. The electrical response of the modified crystals is systematically investigated, and it is found that the (R)-3-aminopiperidine dihydrochloride (API) additive improves the charge collection efficiency and reduces recombination.