Alamo-Nole Luis, Rivera-Rodriguez Glorimar, Santos-Santori Lizette
Department of Natural Sciences, Pontifical Catholic University of Puerto Rico at Ponce, Puerto Rico, USA.
MRS Adv. 2021 May;6(11):291-296. doi: 10.1557/s43580-021-00013-4. Epub 2021 Feb 5.
The key to the success of quantum dots (QDs) within industrial applications is their optical properties. The broad applications of QDs emission wavelengths based on the crystal size can change when they are exposed to different environments like seawater. CdSTe QDs were synthesized in a microwave system at 60, 120, 150, and 180 °C producing different crystal sizes that fluoresce blue (510nm), green (538nm), yellow (566 nm), and red (636nm), respectively. A redshift of the fluorescence indicating possible agglomeration or increase in the crystal size was observed in artificial seawater (40 g/L). Also, a broadening of the emission peaks for the smallest crystals was observed when the CdSTe QDs were in contact with artificial seawater for 72 hours. When A. salina was exposed to CdSTe QDs in artificial seawater, an ingest without loss of fluorescence was observed using fluorescence microscopy. The highest cadmium accumulation (2.2 mg/Kg) into A. salina was observed with the largest crystal synthesized at 180° C, indicating an effect of the crystal size. The small changes and not quenching of the fluorescence in artificial seawater help to understand the behavior of QDs in extreme environments and their applications for photocatalysis in salty environments.
量子点（QDs）在工业应用中取得成功的关键在于其光学性质。基于晶体尺寸的量子点发射波长的广泛应用在暴露于海水等不同环境时可能会发生变化。在微波系统中于60、120、150和180°C合成了CdSTe量子点，产生了分别发出蓝色（510nm）、绿色（538nm）、黄色（566nm）和红色（636nm）荧光的不同晶体尺寸。在人工海水（40g/L）中观察到荧光红移，这表明可能发生了团聚或晶体尺寸增加。此外，当CdSTe量子点与人工海水接触72小时时，观察到最小晶体的发射峰变宽。当盐生杜氏藻暴露于人工海水中的CdSTe量子点时，使用荧光显微镜观察到其摄取且荧光未损失。在180°C合成的最大晶体中观察到盐生杜氏藻中最高的镉积累量（2.2mg/Kg），这表明了晶体尺寸的影响。人工海水中荧光的微小变化且未猝灭有助于了解量子点在极端环境中的行为及其在咸水环境中光催化的应用。
