# Fileset

[SI_ACS_PCDs.pdf](https://mdr.nims.go.jp/filesets/9f2a1731-79fd-44e5-97e2-1ae2478c8733/download)

## Creator

[Barun Kumar Barman](https://orcid.org/0000-0002-9894-1890), [David Hernández-Pinilla](https://orcid.org/0000-0002-9242-7495), [Ovidiu Cretu](https://orcid.org/0000-0002-1822-8172), [Riichiro Ohta](https://orcid.org/0000-0003-2386-9721), Keiko Okano, Toshifumi Shiroya, [Jun Sasai](https://orcid.org/0000-0002-9455-9205), [Koji Kimoto](https://orcid.org/0000-0002-3927-0492), [Tadaaki Nagao](https://orcid.org/0000-0002-6746-2686)

## Rights

This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS Sustainable Chemistry & Engineering, copyright © 2023 American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/acssuschemeng.3c01775[In Copyright](http://rightsstatements.org/vocab/InC/1.0/)

## Other metadata

[New Insight into Fluorescent Polymeric Carbon Dots for Solid-State Laser Device](https://mdr.nims.go.jp/datasets/a4c2be40-0ac0-41e7-9a39-c895ad9d30d1)

## Fulltext

S1  New Insight into Fluorescent Polymeric Carbon Dots for Solid-State Laser Device  Barun Kumar Barman,1*, David Hernández-Pinilla,1*, Ovidiu Cretu,3 Riichiro Ohta,4* Keiko Okano,1 Toshifumi Shiroya,4 Jun Sasai,4 Koji Kimoto,3 and Tadaaki Nagao 1,2*  1International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0044, Japan 2Department of Condensed Matter Physics Graduate School of Science, Hokkaido University, Kita-10 Nishi-8 Kita-ku, Sapporo 060-0810, Japan 3Electron Microscopy Group, National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0044, Japan 4L'Oréal Research and Innovation, KSP R&D, 3-2-1 Sakado, Takatsu-ku, Kawasaki, Kanagawa 213-0012, Japan   *Correspondences  Email: BARMAN.Kumarbarun@nims.go.jp (B.K.B.) mayphys87@gmail.com (D.-H. P) riichiro.ohta@loreal.com (R.O) NAGAO.Tadaaki@nims.go.jp (T.N)  Supporting information includes:  Total number of pages:11  Total number of figures:15  Total number of tables:2    mailto:NAGAO.Tadaaki@nims.go.jpS2                      Figure S1. 1H NMR spectrum of PCDs.                -COOH (Disappeared by adding D2O) S3                   Figure S2. 1H NMR spectrum of CA.  Figure S2. 1H NMR spectrum of CA.  Figure S3. 1H NMR spectrum of CA (citric acid monohydrate).                Figure S3. 1H NMR spectrum of PLys.  Measuring solvent (DMSO-d6) moisture absorption water Measuring solvent (MeOD) S4                   Figure S4. 1H spectrum of PCDs in DMSO and D2O solvents.                   (a) Measuring solvent(DMSO-d6) N-bonded alkyl  -NCH2, etc  ● Derived from citric acid ◆ Disappeared peak by adding D2O (Possibility of polar functional groups)  Measuring solvent (DMSO-d6)  Alkyl Ch3, CH2, CH O-bonded alkyl ethers, alcohols, esters, etc Olefin C=C-H, C=C(H)H, etc O-bonded alkyl ethers, alcohols, esters, etc S5                     Olefin                Figure S5. 13C NMR spectra of (a) CA, (b) PLys, and (c) PCDs. (c) (b) Measuring solvent(MeOD) ● Derived from citric acid Olefin Alkyne ? derived from aromatics Alkyl N,O bound alkyl S6                   Figure S6. 13C NMR spectra of osmosis purified PCDs in D2O solvent.                  Figure S7. Comparison of Raman spectra of dried PLys and PCDs films on quartz substrate.  1000 1200 1400 1600 1800 2000C-C stretching modes PLys PCDsIntensity (a.u.)Raman shift (cm-1)Amide-IAmide-IIIMethylene bending modeS7             Figure S8. DLS spectra of PCDs synthesized at (a) 200 0C and (b) 220 0C.                Figure S9. Typical TEM images of PCDs on superhigh resolution carbon coated Cu grid, where thickness of the carbon layer ~ 6-10 nm, which hinder the observations soft PCDs in the size range of 5-10 nm.            (a) (b) S8                                Figure S10. AFM images of PCDs and their corresponding height profile at two different areas.       S9               Figure S11. Comparison of UV-vis absorbance spectra of 0.01 wt.% PCDs solution synthesized at different temperatures.                 Figure S12. Digital photograph of solid PCDs and its emission in solid-state by UV (365 nm) light excitation.    200 300 400 500 6000.00.20.4AbsorbanceWavelength (nm) PCDs- 180 ℃ PCDs- 200 ℃ PCDs- 220 ℃S10            Figure S13. (a and b) PLQY of PCDs aqueous solution by 365 nm UV light excitation within 5days interval.               Figure S14. (a and b) Photoluminescence stability of PCDs in aqous solution and glass coated solid-film by continuous irradiation of 365 nm UV light for 2 h.           (a) (b) 400 450 500 550 600 6500100200300400500PL Intensity (a.u.)Wavelength (nm) 0 h 1 h 2 h400 450 500 550 600 6500500100015002000PL Intensity (a.u.)Wavelength (nm) 0 h (PLQY:49 %) 1 h (PLQY:47 %) 2 h (PLQY:45 %)S11            Figure S15. Experimental and fitted TRPL spectra of (a) PCDs dispersion and (b) film.   Table S1 The results of CHNO elemental analysis of PLys and PCDs Sample name C (wt.%) H (wt.%) N (wt.%) O (wt.%) C:H:N:O (atomic ratio) PLys 55.52 9.71 21.56 12.65 4.62:9.71:1.54:0.78 PCDs 45.99 5.38 6.29 42.44 3.83: 5.38:0.44:2.68  Table S2. PL decay lifetimes and fitting parameters of PCDs dispersion and solid film  Sample name 1 (ns) A1 (%)  (ns) A2 (%) avg (ns) Dispersion 0.464 55.7 8.15 44.3 7.63 Film 0.296 96 3.081 4 1.1  The average PL lifetime (avg) was obtained from the bi-exponential fitted time decay spectra using the following equation: avg = (A1  + A2  )( A1 + A2)  where A1, and A2 are the amplitudes, and τ1 and τ2 are the PL decay times.