Dual-Doped Nickel Sulfide for Electro-Upgrading Polyethylene Terephthalate into Valuable Chemicals and Hydrogen Fuel

Zhijie Chen; Renji Zheng; Teng Bao; Tianyi Ma; Wei Wei; Yansong Shen; Bing-Jie Ni

doi:10.1007/s40820-023-01181-8

Dual-Doped Nickel Sulfide for Electro-Upgrading Polyethylene Terephthalate into Valuable Chemicals and Hydrogen Fuel

Nanomicro Lett. 2023 Sep 11;15(1):210. doi: 10.1007/s40820-023-01181-8.

Authors

Zhijie Chen¹, Renji Zheng², Teng Bao³, Tianyi Ma⁴, Wei Wei¹, Yansong Shen⁵, Bing-Jie Ni⁶

Affiliations

¹ Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NSW, 2007, Australia.
² School of Minerals Processing and Bioengineering, Central South University, Changsha, 410083, People's Republic of China. zhengrj@csu.edu.cn.
³ School of Biology, Food and Environment Engineering, Hefei University, Hefei, 230601, People's Republic of China.
⁴ School of Science, STEM College, RMIT University, Melbourne, VIC, 3000, Australia.
⁵ School of Chemical Engineering, University of New South Wales, Sydney, NSW, 2052, Australia.
⁶ Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NSW, 2007, Australia. bingjieni@gmail.com.

Abstract

Electro-upcycling of plastic waste into value-added chemicals/fuels is an attractive and sustainable way for plastic waste management. Recently, electrocatalytically converting polyethylene terephthalate (PET) into formate and hydrogen has aroused great interest, while developing low-cost catalysts with high efficiency and selectivity for the central ethylene glycol (PET monomer) oxidation reaction (EGOR) remains a challenge. Herein, a high-performance nickel sulfide catalyst for plastic waste electro-upcycling is designed by a cobalt and chloride co-doping strategy. Benefiting from the interconnected ultrathin nanosheet architecture, dual dopants induced up-shifting d band centre and facilitated in situ structural reconstruction, the Co and Cl co-doped Ni₃S₂ (Co, Cl-NiS) outperforms the single-doped and undoped analogues for EGOR. The self-evolved sulfide@oxyhydroxide heterostructure catalyzes EG-to-formate conversion with high Faradic efficiency (> 92%) and selectivity (> 91%) at high current densities (> 400 mA cm^-2). Besides producing formate, the bifunctional Co, Cl-NiS-assisted PET hydrolysate electrolyzer can achieve a high hydrogen production rate of 50.26 mmol h^-1 in 2 M KOH, at 1.7 V. This study not only demonstrates a dual-doping strategy to engineer cost-effective bifunctional catalysts for electrochemical conversion processes, but also provides a green and sustainable way for plastic waste upcycling and simultaneous energy-saving hydrogen production.

Keywords: Electro-upcycling; Hydrogen energy; Organic waste upcycling; Structural reconstruction; d Band centre.