biostudies-literatureUnknown16(4)Zhang QClusteroluminescence in non-conjugated systems has garnered significant attention for the development of advanced light-emitting materials, however, the understanding of the underlying mechanism remains a challenge. Herein, we report a facile, one-step strategy to prepare unconventional dual-mode luminescent materials by thermal treatment of aqueous citric acid (CA) and l-lysine (Lys). These materials exhibit bright fluorescence (The quantum yield is up to 43.2%) and remarkably long-lived room-temperature phosphorescence (RTP, up to 5 s). Combined experimental characterization and theoretical calculations were used to reveal the underlying dual emission mechanisms. Theoretical calculations revealed a reduced HOMO-LUMO energy gap upon blending of the CA and Lys and formation of ionic interaRSC advances2973-2980https://www.ebi.ac.uk/biostudies/studies/S-EPMC12797206biostudies-literatureMolecular mechanism of biocompatible clusteroluminogens from citric acid and l-lysine.PMC12797206Sun PLi BZhang QfalseMolecular mechanism of biocompatible clusteroluminogens from citric acid and l-lysine.Clusteroluminescence in non-conjugated systems has garnered significant attention for the development of advanced light-emitting materials, however, the understanding of the underlying mechanism remains a challenge. Herein, we report a facile, one-step strategy to prepare unconventional dual-mode luminescent materials by thermal treatment of aqueous citric acid (CA) and l-lysine (Lys). These materials exhibit bright fluorescence (The quantum yield is up to 43.2%) and remarkably long-lived room-temperature phosphorescence (RTP, up to 5 s). Combined experimental characterization and theoretical calculations were used to reveal the underlying dual emission mechanisms. Theoretical calculations revealed a reduced HOMO-LUMO energy gap upon blending of the CA and Lys and formation of ionic intera2026-01-01T00:00:00Z2026 Jan2026-06-09T05:38:35.32Z2026-06-09T03:07:42.16ZS-EPMC127972064153647210.1039/d5ra09240j