In this study, we propose a novel approach for the synthesis of AISe core and highly luminescent AISe/ZnS core/shell NCs in a 2-step procedure. First, the AISe core NCs were produced using both glutathione and citric acid as dual stabilizers at 96 °C for 20 min at different pH values of the reaction solution. | Vietnam Journal of Science and Technology 62 2 2024 288-298 doi 2525-2518 18628 Aqueous synthesis of highly luminescent AgInSe2 ZnS core shell nanocrystals Tran Thi Thu Huong1 Nguyen Thi Hiep2 3 Nguyen Thu Loan1 Le Van Long1 Nguyen Thanh Tung1 Ung Thi Dieu Thuy1 Peter Reiss4 Jae Yup Kim5 Nguyen Quang Liem1 1 Institute of Materials Science Vietnam Academy of Science and Technology 18 Hoang Quoc Viet Cau Giay Ha Noi Viet Nam 2 Institute of Research and Development Duy Tan University Da Nang City Viet Nam 3 Faculty of Natural Sciences Duy Tan University Da Nang City Viet Nam 4 University of Grenoble Alpes CEA CNRS IRIG-SyMMES STEP 38000 Grenoble France 5 Department of Chemical Engineering Dankook University Yongin 16890 Republic of Korea Email dieuthuy@ Received 7 August 2023 Accepted for publication 27 February 2024 Abstract. Ternary I-III-VI chalcopyrite-type nanocrystals NCs range among the most important alternative materials to Cd-based NCs. Within this materials family AgInSe2 AISe presents a narrower bandgap than widely studied AgInS2 AIS making it more suitable for numerous applications. At present it remains a long-standing challenge to directly synthesize high-quality AISe core and AISe ZnS core shell NCs in aqueous solution at atmospheric pressure. In this work we describe their synthesis using glutathione and citric acid as dual stabilizers. First to form AISe core NCs the Se precursor is injected into a solution containing the Ag and In complexes at 96 C for 20 min. In the second step the AISe ZnS core shell structure is created by growing the ZnS shell on the AISe NCs surface at 90 C for 60 min. The synthesized AISe and AISe ZnS core shell NCs are characterized using X-ray diffraction transmission electron microscopy and UV-Vis absorption and photoluminescence for optical spectroscopies. After the growth of the ZnS shell AISe ZnS core shell NCs exhibit higher photostability and emit intense luminescence at a wavelength of 680 nm with
