Yadav Jeetika, Liang Qiaoli, Pan Shanlin
Department of Chemistry and Biochemistry, The University of Alabama, Tuscaloosa, Alabama 35487-0336, United States.
ACS Appl Mater Interfaces. 2020 Jun 17;12(24):27443-27452. doi: 10.1021/acsami.0c01050. Epub 2020 Jun 3.
Lead-based perovskite MAPbX (MA = CHNH, X = Cl and Br) has shown great potential benefits to advance modern optoelectronics and clean energy harvesting devices. Poor structural stability is one of the major challenges of MAPbX perovskite materials to overcome to achieve desired device performance. Here, we present the electrochemical stability study of CHNHPbClBr quantum dots (QDs) by electrogenerated chemiluminescence (ECL) and photoluminescence (PL) spectroelectrochemistry methods. Electrochemical anodization of pristine MAPbX QD film results in the disproportionate loss of methylammonium and halide ions (X = Cl and Br). ECL efficiency and stability of perovskite QDs in the presence of coreactant tripropyl amine (TPrA) can be greatly improved after being incorporated into a polystyrene (PS) matrix. Mass spectrum and X-ray photoelectron spectroscopy (XPS) measurements were used to provide chemical composition variation details of QDs, which are responsible for the ECL and PL characteristics (e.g., wavelength redshift) of perovskite QDs in an electrochemical cell.
含铅钙钛矿MAPbX（MA = CH₃NH₂，X = Cl和Br）在推动现代光电子学和清洁能源收集设备方面已显示出巨大的潜在优势。结构稳定性差是MAPbX钙钛矿材料要实现理想器件性能需克服的主要挑战之一。在此，我们通过电化学发光（ECL）和光致发光（PL）光谱电化学方法对CH₃NH₂PbClBr量子点（QDs）进行了电化学稳定性研究。原始MAPbX量子点薄膜的电化学阳极氧化导致甲铵离子和卤离子（X = Cl和Br）不成比例地损失。在掺入聚苯乙烯（PS）基质后，钙钛矿量子点在存在共反应剂三丙胺（TPrA）时的ECL效率和稳定性可得到极大提高。使用质谱和X射线光电子能谱（XPS）测量来提供量子点的化学成分变化细节，这些细节决定了电化学电池中钙钛矿量子点的ECL和PL特性（如波长红移）。
