Article, 2024

Encapsulation of carbon-nanodots into metal-organic frameworks for boosting photocatalytic upcycling of polyvinyl chloride plastic

In: Applied Catalysis B Environmental, ISSN 0926-3373, Volume 341, 10.1016/j.apcatb.2023.123355

Contributors (8)

Qin J. [1] Dou Y. (0000-0003-0802-9898) (Corresponding author) [2] Zhou J. [2] Zhao D. (0000-0003-3822-1418) [1] Orlander T. (0000-0001-8701-5376) [1] Andersen H.R. [1] Helix-Nielsen C. (0000-0002-9392-7133) [1] Zhang W. (0000-0002-5011-1951) [1]

Affiliations

  1. [1] Technical University of Denmark
  2. [NORA names: DTU Technical University of Denmark; University; Denmark; Europe, EU; Nordic; OECD]
  3. [2] Beijing University of Chemical Technology
  4. [NORA names: China; Asia, East]

Abstract

Although polyvinyl chloride (PVC) ranks as the third most mass-produced synthetic plastic, the chemical upcycling of non-biodegradable PVC waste remains a significant challenge. Herein, carbon nanodots combined with the metal-organic framework (CDs/Zr-MOF) are fabricated for photocatalytic upcycling of PVC. Specifically, the ultra-small-sized CDs (∼2.0 nm) are encapsulated into Zr-MOF pores via a mild pyrolysis strategy. The maintained MOF structure facilitates charge/mass transfer and improves the surface-to-volume ratio of active sites of CDs. The CDs/Zr-MOF exhibits high activity for PVC conversion of ∼76.5% towards acetic acid with a yield of ∼14%. The mechanism investigation indicates the generated •OH radicals can efficiently trigger cleavage of C-Cl/C-C bonds of PVC. Moreover, the reduction of the energy barrier for the hydroxylation reaction as a rate-limiting step contributed to improved PVC conversion performance. This work offers a feasible method for fabricating nanoparticle-embedded MOF-based photocatalysts and provides new insights into the chemical upcycling of plastics.

Keywords

Acetic acid, CDs/Zr-MOF photocatalyst, Mild pyrolysis, Polyvinyl chloride

Funders

  • Innovation Fund Denmark Grand Solution
  • China Scholarship Council
  • Novo Nordisk Fonden
  • Fundamental Research Funds for the Central Universities
  • Danmarks Tekniske Universitet
  • National Natural Science Foundation of China