Extraction of High-Quality Quantum Dot Photocatalysts via Combination of Size Selection and Electrochemiluminescence

摘要： Quantum dots (QDs) represent one of the most promising photocatalytic systems for solar hydrogen production. Tremendous works have been devoted to the design of QDs photocatalysts, but their further development is limited by the unwanted mix of high- and low-quality QDs with different activities. With multinary Ag-In-Zn-S (AIZS) QDs as an example, here, we present a simple method for the extraction and screening of efficient photocatalysts by combination of gradient centrifugation and electrochemiluminescence (ECL). With controllable introduction of poor solvent, the crude QDs were separated into five individual samples by gradient centrifugation, from which ECL tests were performed to get the surface state information for photocatalyst screening. By the combination of size-selective centrifugation and ECL screening, we were able to get the high-activity component (AIZS-#4), which achieved 1.68 mmol·g?1 h?1, 6 times higher than that of the initial AIZS QDs. This work provides an alternative useful pathway for obtaining high-quality QD photocatalysts, beyond pursuing of perfect synthetic conditions.