Oxygen-enriched carbon quantum dots from coffee waste: Extremely active organic photocatalyst for sustainable solar-to-H2O2 conversion

Do-Yeon Lee; Zeeshan Haider; Siva Kumar Krishnan; Thamaraiselvi Kanagaraj; Sang Hwan Son; Jungho Jae; Jung Rae Kim; Paskalis Sahaya Murphin Kumar; Hyoung-Il Kim

doi:10.1016/j.chemosphere.2024.142330

Oxygen-enriched carbon quantum dots from coffee waste: Extremely active organic photocatalyst for sustainable solar-to-H₂O₂ conversion

Chemosphere. 2024 May 15:361:142330. doi: 10.1016/j.chemosphere.2024.142330. Online ahead of print.

Authors

Do-Yeon Lee¹, Zeeshan Haider², Siva Kumar Krishnan³, Thamaraiselvi Kanagaraj⁴, Sang Hwan Son⁵, Jungho Jae⁶, Jung Rae Kim⁷, Paskalis Sahaya Murphin Kumar⁸, Hyoung-Il Kim⁹

Affiliations

¹ Department of Civil and Environmental Engineering, Yonsei University, 50 Yonsei-ro, Seoul, 03722, Republic of Korea. Electronic address: lakesis1@yonsei.ac.kr.
² Department of Civil and Environmental Engineering, Yonsei University, 50 Yonsei-ro, Seoul, 03722, Republic of Korea; Department of Physics, Incheon National University, 119-Academy-ro, Yeonsu-gu, Incheon, 22012, Republic of Korea. Electronic address: chemistudent@gmail.com.
³ CONACYT-Instituto de Física, Benemérita Universidad Autosome de Puebla, Apdo. Postal J-48, Puebla, 72570, Mexico. Electronic address: Sivakumar@ifuap.buap.mx.
⁴ Department of Biomaterials, Saveetha Dental College and Hospital, SIMATS, Saveetha University, Chennai, 600077, India. Electronic address: tsthamarai89@gmail.com.
⁵ Department of Chemical and Biomolecular Engineering, Pusan National University, Busan, 46241, Republic of Korea. Electronic address: shson@pusan.ac.kr.
⁶ Department of Chemical and Biomolecular Engineering, Pusan National University, Busan, 46241, Republic of Korea. Electronic address: jh.jae@pusan.ac.kr.
⁷ Department of Chemical and Biomolecular Engineering, Pusan National University, Busan, 46241, Republic of Korea. Electronic address: j.kim@pusan.ac.kr.
⁸ Department of Civil and Environmental Engineering, Yonsei University, 50 Yonsei-ro, Seoul, 03722, Republic of Korea; Department of Chemical Engineering, National Chung Cheng University, Chia-Yi, 62102, Taiwan; Advanced Institute of Manufacturing with High-Tech Innovations, National Chung Cheng University, Chia-Yi, 62102, Taiwan. Electronic address: marpinindian@gmail.com.
⁹ Department of Civil and Environmental Engineering, Yonsei University, 50 Yonsei-ro, Seoul, 03722, Republic of Korea; Future City Open Innovation Center, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea. Electronic address: hi.kim@yonsei.ac.kr.

PMID: 38759805
DOI: 10.1016/j.chemosphere.2024.142330

Abstract

Solar-driven artificial photosynthesis offers a promising avenue for hydrogen peroxide (H₂O₂) generation, an efficient and economical replacement for current methods. The efficiency and selectivity hurdles of the two-electron oxygen reduction reaction (ORR) in solar-to- H₂O₂ conversion are substantial barriers to large scale production. In this manuscript, a simple biomass-assisted synthesis was performed to produce oxygen-enriched carbon quantum dots (OE-CQDs) from spent coffee waste, acting as an efficient photocatalyst for solar-powered H₂O₂ production. OE-CQDs can stabilize and store light-generated electrons effectively, boosting charge separation and enhancing photocatalytic performance with longevity. The maximal photocatalytic H₂O₂ production was achieved viz the utilization of OE-CQDs with generation rate of 356.86 μmol g^-1 h^-1 by retaining 80% activity without any external sacrificial donors. The outstanding performance of synthesized OE-CQDs under light exposure at wavelength (λ) of 280 nm has been ensured by the quantum yield value of 9.4% upon H₂O₂ generation. The combinatorial benefits of OE-CQDs with their authentic crystalline structure and oxygen enrichment, is expected to be enhancing the ORR activity through accelerating charge transfer, and optimizing oxygen diffusion. Consequently, our eco-friendly method holds considerable promise for creating highly efficient, metal-free photocatalysts for artificial H₂O₂ production.

Keywords: Coffee waste; H(2)O(2) generation; Oxygen-enriched carbon quantum dots; Photocatalyst; Solar-driven photosynthesis.