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The escalating plastic pollution and potential energy crisis necessitate upcycling plastic waste into high-value-added chemicals and fuels. Combining the hydrogen evolution reaction (HER) with a thermodynamically feasible and sustainable anodizing reaction provides a sustainable option for the electrochemical appreciation of plastic waste. Herein, a hybrid electrocatalyst, i.e., PdFe alloy nanoparticles supported on nitrogen-doped carbon nanotubes (denoted as PdFe/N-CNTs), is proposed for the electrochemical upcycling of polyethylene terephthalate (PET) waste at the anode with simultaneous generation of hydrogen at the cathode. Benefiting from the distinctive structural characteristics of N-doped carbon nanotubes and downshift in the d-band center created by alloying Fe with Pd, the resultant PdFe/N-CNT bifunctional catalyst exhibits superior electrocatalytic performance for both the ethylene glycol oxidation reaction (EGOR) and the HER in 1.0 M KOH electrolyte, affording low overpotentials of 32 mV (vs. RHE)@10 mA cm−2 and 1.22 V (vs. RHE)@10 mA cm−2 for the respective HER and EGOR with a high faradaic efficiency (FE) of 87% for formate production. Besides, a two-electrode integrated system is constructed by coupling PET hydrolysate oxidation with the HER, which not only enables the concurrent generation of formate acid (FA) at the anode and H2 at the cathode but also achieves a current density of 500 mA cm−2 at a cell voltage of 1.68 V, lower than that of conventional water splitting. The conversion of PET into FA is studied by in situ electrochemical Fourier-transform infrared (FTIR) spectroscopy measurements and density functional theory (DFT). This work is expected to provide meaningful guidance for the upcycling of PET plastic waste by rationally designing highly efficient electrocatalysts. [ABSTRACT FROM AUTHOR]

Faced with the forthcoming tide of retired lithium‐ion batteries (LIBs), it is imperative to explore effective regeneration and upcycling strategies to alleviate the resource shortage, address environmental pollution, and cater to the demand for high‐energy‐density cathode materials. Herein, a facile, non‐constructive, one‐stone‐for‐three‐birds solid‐phase sintering strategy is proposed to regenerate the degraded LiCoO2 (D‐LCO) cathode and even upgrade its stability at high voltages, in which three birds, i.e., lithium supplement, Li2SO4 coating, and Mn doping into Co sites while N, S doping into Li‐O slabs are simultaneously hit with one stone (one‐pot solid‐phase sintering). Benefiting from these favorable characteristics, the upcycled cathode not only yields high discharge‐specific capacity of 188.2 mAh g−1 at 0.2 C, but also delivers superior cycling performance with 92.5% of capacity retention after 100 cycles (86.4% after 300 cycles) at 0.5 C and excellent rate capability at a high cutoff voltage of 4.5 V, superior to a freshly commercial counterpart. This work is expected to provide meaningful guidance for the upcycling of D‐LCO into high‐energy‐density batteries with long‐term cycling stability. [ABSTRACT FROM AUTHOR]

Wood-based adsorbents have important engineering significance in removing toxic heavy metals from wastewater due to their natural abundance, sustainability and biodegradability together with superior sorption performance. Herein, a novel adsorbent, lignosulfonate functionalized g-C3N4/carbonized wood sponge (denoted as LS-C3N4/CWS), has been successfully fabricated through pyrolysis of urea impregnated wood sponge under an argon atmosphere, followed by subsequent modification with lignosulfonate (LS). As expected, the resulting LS-C3N4/CWS shows excellent decontamination capability toward Pb2+, Cd2+ and Cu2+ with high uptake capacities of 659.6, 329.1 and 173.5 mg g−1, respectively, outperforming most of the previously reported wood-based adsorbents and other nanomaterials. Moreover, the spent LS-C3N4/CWS can be readily recovered and maintains high removal efficiency after ten adsorption–regeneration cycles, revealing its excellent recyclability. Significantly, LS-C3N4/CWS can be directly utilized as an ultrafiltration membrane to continuously treat large volumes of simulated wastewater (9550 mL g−1 for Pb2+, 1500 mL g−1 for Cd2+ and 8700 mL g−1 for Cu2+) to below the permitted level in drinking water. The superior decontamination performance coupled with facile separation, cost-effectiveness and no secondary pollution underscores the huge potential of LS-C3N4/CWS in effectively removing heavy metals from polluted waters. [ABSTRACT FROM AUTHOR]

The emerging market demand for high-energy-density of energy storage devices is pushing the disposal of end-of-life LiCoO 2 (LCO) to shift toward sustainable upgrading into structurally stable high-voltage cathode materials. Herein, an integrated bulk and surface commodification strategy is proposed to render spent LCO (S-LCO) to operate at high voltages, involving bulk Mn doping, near surface P gradient doping, and Li 3 PO 4 /CoP (LPO/CP) coating on the LCO surface to yield upcycled LCO (defined as MP-LCO@LPO/CP). Benefiting from hybrid surface coating with Li + -conductive Li 3 PO 4 (LPO) and electron conductive CoP (CP) coupled with Mn and P co-doping, the optimized MP-LCO@LPO/CP cathode exhibits enhanced high-voltage performance, delivering an initial discharge capacity of 218.8 mAh g -1 at 0.2 C with excellent capacity retention of 80.9% (0.5 C) after 200 cycles at a cut-off voltage of 4.6 V, along with 96.3% of capacity retention over 100 cycles at 4.5 V. These findings may afford meaningful construction for the upcycling of commercial S-LCO into next-generation upmarket cathode materials through the elaborate surface and bulk modification design., (© 2024 Wiley‐VCH GmbH.)