Photoelectrochemical performance of ligand-free CsPb₂Br₅ perovskites

Abstract

Herein, we have developed a method for the facile aqueous synthesis of ligand-free cesium lead halide perovskite nanoplatelets with pure CsPb2Br5. The ligand-free CsPb2Br5 nanoplatelets showed good environmental stability, green...

Water-stable perovskite CsPb2Br5/CdSe quantum dot-based photoelectrochemical sensors for the sensitive determination of dopamine

“…The absorption spectra of CdSe and CsPb 2 Br 5 were converted into Tauc plots to determine the optical band gap ( E g ) using the following Kubelka–Munk equation: 30 αhv = A ( hv − E g ) 2 where hv , α , and A represent the photon energy, absorption coefficient, and proportionality constant, respectively. As shown in Fig.…”

“…S5,† the optical band gaps of CdSe and CsPb 2 Br 5 were determined to be 1.96 eV and 3.45 eV, respectively, which are in good agreement with previous reports. 30,34 Based on the relationship between the conduction band edge ( E CB ), valence band edge ( E VB ), and band gap ( E g ): E VB = E CB + E g , E VB for CdSe and E CB for CsPb 2 Br 5 were determined to be 0.65 V and −2.15 V ( vs. NHE), respectively. So the energy band structures of the CdSe quantum dots and perovskite CsPb 2 Br 5 are illustrated in Fig.…”

“…S5, † the optical band gaps of CdSe and CsPb 2 Br 5 were determined to be 1.96 eV and 3.45 eV, respectively, which are in good agreement with previous reports. 30,34 Based on the relationship between the conduction band edge (E CB ), valence band edge (E VB ), and band gap (E g ):…”

“…The energy level of DA is situated at −4.91 eV, precisely located above the valence band of CsPb 2 Br 5 (−5.74 eV), 10,30 making it a promising candidate for a DA PEC sensor. Furthermore, CdSe quantum dots can passivate the surface defects of CsPb 2 Br 5 , which not only accelerates the transfer and separation of photogenerated charge carriers but also enhances the stability of the perovskite.…”

Sizeable square CsPb2Br5 nanosheets for photodetection

“…25 Recent studies have shown that aqueous solvents are effective in enhancing the crystal quality and grain size of CsPb 2 X 5 . 24,26 Regrettably, in prior research, the high supersaturation of precursors within aqueous solutions compromised the stability of the growth medium. This resulted in accelerated nuclei growth, consequently yielding numerous small single crystals.…”