Abstract:
Colloidal two-dimensional (2D) nanoplatelets (NPLs) have been extensively studied owing to promising potential in optoelectronic applications. Here, we have reported the preparation of 2D CdSeTe alloy NPLs and investigated their energy and charge transfer with porphyrin molecules. The red shifting in the optical properties suggests the change in the band gaps. Furthermore, the energy and the charge transfer are evident in the composite of CdSeTe alloy NPLs with 5,10,15,20-tetra(4pyridyl)-porphyrin (TpyP) molecules. The quenching in the photoluminescence (PL) spectra and PL decay time supports the energy transfer (~61 % efficiency) and the charge transfer. The thermodynamically feasible hole transfer is evidenced by the band alignment of the alloy NPLs and TpyP molecules, which is further supported by a transient absorption spectroscopy (TAS) study. The TA study found the hole transfer within ~3 ps time scale, proving the effective charge carrier separation for better optoelectronic applications.
摘要:
胶体二维(2D)纳米片(NPL)由于在光电应用中的潜力而得到了广泛的研究。这里,我们已经报道了二维CdSeTe合金NPL的制备,并研究了它们与卟啉分子的能量和电荷转移。光学性质的红移表明带隙的变化。此外,在CdSeTe合金NPL与5,10,15,20-四(4吡啶基)-卟啉(TpyP)分子的复合材料中,能量和电荷转移很明显。光致发光(PL)光谱和PL衰减时间中的猝灭支持能量转移(〜61%效率)和电荷转移。合金NPL和TpyP分子的能带排列证明了热力学上可行的空穴转移,瞬态吸收光谱(TAS)研究进一步支持。TA研究发现空穴转移在~3ps时间尺度内,证明有效的电荷载流子分离更好的光电应用。