Efficient Electrocatalytic Upcycling of Polybutylene Terephthalate Plastics via Mn-Doped Ni-MOF Nanosheet Arrays

Electrochemical upcycling of waste poly(butylene terephthalate) (PBT) offers a promising strategy for sustainable plastic valorization. In this study, we synthesized a self-supported Mn-doped Ni-MOF nanosheet electrode on nickel foam (MnNi-MOF/NF) via hydrothermal synthesis. This bifunctional electrode drives the hydrogen evolution reaction (HER) at the cathode and the PBT-derived 1,4-butanediol oxidation reaction (BOR) at the anode. During electrochemical operation, MnNi-MOF/NF in situ forms Mn-Ni(OH) 2 and Mn-NiOOH, both of which are the true active species for HER and BOR. Mn doping optimizes the d-band center of Ni, strengthening adsorption of intermediates and boosting activity for both reactions. Experimental results show that the catalyst requires 143 mV to reach 10 mA cm –2 in HER and delivers 100 mA cm –2 at 1.33 V in BOR. Meanwhile, the Faradaic efficiency for succinic acid production reaches 93.83%. This strategy enables effective waste conversion and sustainable recycling through green processes.