Polyethylene terephthalate (PET) is one of the most abundant polyester wastes, and its efficient upcycling remains a major challenge for circular materials management. Chemical upcycling, particularly alkaline hydrolysis, converts PET into terephthalate and ethylene glycol (EG), however, the water-soluble feature of EG complicates its separation from PET hydrolysates. Direct electrooxidation of PET-derived EG therefore provides an attractive route for coupling plastic valorization with cathodic hydrogen evolution. EG oxidation can proceed through C2-preserving pathways toward glycolate or through C-C-cleavage pathways to formate, which could be substantially converted to value-added glycolic acid or potassium diformate. Achieving selective conversion requires simultaneous control of hydroxyl activation, adsorption of oxygenated C2 intermediates, C-C bond retention or cleavage, and catalyst reconstruction under anodic conditions. This review summarizes recent advances in electrocatalytic upcycling of PET-derived EG, with emphasis on the mechanistic origins of glycolate and formate selectivity. Then, we introduce the electrocatalyst engineering strategies as guided by the mechanisms, including interfacial, alloying, strain, reconstruction, defect, and multicomponent (high entropy) engineering strategies in addition to their roles in regulating surface electronic structure, *OH adsorption and intermediates conversion. Finally, we outline opportunities for non-noble-metal catalysts for C2 pathway, dynamic potential pulse control, advanced in-situ characterizations and data-driven discovery of electrocatalysts.

The efficient electrosynthesis of urea from CO₂ and NO₃⁻ relies on the suppression of the competitive hydrogen evolution reaction (HER), especially the Tafel and Heyrovsky steps. We designed CuNi alloyed structure encapsulated into nitrogen doped carbon nanotubes (CuNi-NCNT) for superior urea electrosynthesis. The interstitial Cu atom breaks the successive hydrogen binding active sites, Ni atoms, as NO₃⁻ and CO₂ strongly adsorb on Cu sites, hindering the Tafel step of HER. Besides, due to the steric effect, the Heyrovsky step is also restrained. Thus, the HER catalysis is well suppressed, leading to a high Faradaic efficiency (33.6%) of urea electrochemical synthesis for CuNi-NCNT at −0.4 V vs. reversible hydrogen electrode (RHE) associated with yielding rate of 5.3 mmol·h⁻¹·g_cat⁻¹, boosted by factors of 6.7 and 4.4 with relative to Ni-NCNT and metallic Cu, respectively. The in-situ Raman spectroscopy and integrated crystal orbital Hamilton population (ICOHP) theoretical calculation indicate that Ni sites strongly adsorb hydrogen atom for hydrogeneration, while CO₂ and NO₃⁻ are electrochemically bound with Cu atoms, synergistically contributing to the efficient urea formation. Moreover, the in-situ Raman spectroscopy suggests the reaction pathway of urea electrosynthesis via the formation of *NH₂ and *CO species from NO₃⁻ and CO₂. Consequently, a lowered energy barrier for C–N coupling (0.55 eV) can be achieved on CuNi compared to Cu(111) and Ni(111). This work offers significant insights into the critical roles of Cu and Ni in urea electrosynthesis and promotion in catalytic activity in Cu-system.