Polyethylene terephthalate (PET) plastic has been extensively used in our social life, but its poor biodegradability has led to serious environmental pollution and aroused worldwide concern. Up to now, various strategies have been proposed to address the issue, yet such strategies remain seriously impeded by many obstacles. Herein, waste PET plastic was selectively carbonized into three-dimensional (3D) porous carbon nanosheets (PCS) with high yield of 36.4 wt%, to be further hybridized with MnO₂ nanoflakes to form PCS-MnO₂ composites. Due to the introduction of an appropriate amount of MnO₂ nanoflakes, the resulting PCS-MnO₂ composite exhibited a specific capacitance of 210.5 F g⁻¹ as well as a high areal capacitance of 0.33 F m⁻². Furthermore, the PCS-MnO₂ composite also showed excellent cycle stability (90.1% capacitance retention over 5000 cycles under a current density of 10 A g⁻¹). The present study paved an avenue for the highly efficient recycling of PET waste into high value-added products (PCSs) for electrochemical energy storage.

Ultrasensitive visual detection of hydrazine hydrate using a Au nanoparticles-based colorimetric sensing system (ANCSS) is reported for the first time, which is based on the hydrogen bonding recognition and the modality change of hydrogen bonding from “linear” (simple hydrogen bond interactions) to “nonlinear” (a complicated hydrogen bond network) between as-modified Au nanoparticles (Au NPs).

The emerging two-dimensional monoelemental materials (2D Xenes) have been commonly supposed as promising drug delivery carriers, photothermal and photodynamic therapeutic agents, biosensors, theranostics, and some other candidates for biomedical applications. Here, high-performance and bioactive ultrathin 2D Tellurium nanosheets (Te NSs) are prepared by a simple but efficient liquid-phase exfoliation approach. The as-obtained Te NSs possess a mean size of ∼90 nm and a mean thickness of ∼5.43 nm. The pegylation Te NSs (Te-PEG NSs) possess excellent biocompatibility and stability. The Te-PEG NSs could generate local hyperthermia with a remarkable photothermal conversion efficiency of about 55% under 808 nm laser irradiation. Additionally, Te-PEG NSs exhibit an extremely high loading capacity of chemo drug (∼162%) owing to their ultra-high surface area and tumor microenvironment-triggered drug release superiority. The results of in vivo experiments show that the Te-PEG NSs have higher tumor elimination efficiency via the combination of photothermal and chemotherapy, comparing to any other single therapeutic modalities. Therefore, our work not only highlights the promising potentials of tellurene as an ideal anti-cancer platform but also expands the application of 2D Te for cancer nanomedicine.