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Seawater desalination (SD) is regarded as one of the most effective solutions to the shortage of fresh water in many desert and island areas. However, high energy consumption and environmental pollution impede its development. Herein, a self-powered seawater desalination (SP-SD) system is proposed to reduce energy consumption and environmental pollution by using a wind-driven radial-arrayed rotary triboelectric nanogenerator (RAR-TENG). As expected, the SP-SD unit achieves a high desalination capacity of 10.5 mg/h for the 0.17 M NaCl solution at a rotation speed of 350 rpm with a hydrogen (H 2 ) production rate of 5.6 × 10 -4 mL/s, which is superior to most previous reported results. Moreover, the SP-SD system could easily reach a desalination capacity of 2.4 mg/h at a low wind speed of 6 m/s by using natural wind energy. This wind-driven SP-SD system contributes an innovative approach to the field of environmental electrochemistry.

In this work, we fabricated cobalt-doped carbon quantum dots (Co-CQDs) by a one-pot hydrothermal method with cobalt tetraphenylporphyrin and 1,2-ethanediamine as precursors. The morphology and structure of the Co-CQDs were characterized through transmission electron microscopy, X-ray diffraction spectra, Fourier transform infrared, and X-ray photoelectron spectra. The Co-CQDs emitted intense blue luminescence under ultraviolet irradiation and exhibited a typical excitation-dependent emission property. Moreover, they can act as a fluorescent probe for the detection of Fe 3+ and ascorbic acid (AA) with high selectivity and sensitivity through an "on-off-on" mode. The limit of detection (LOD) of Fe 3+ was measured as 38 μM (S/N = 3). The quenched emission of carbon quantum dots can be recovered with the addition of ascorbic acid (AA) to the Co-CQDs/Fe 3+ system. The change of fluorescence was linear with the concentration of AA (0.6-1.6 mM) with the LOD of 18 μM. Furthermore, the Co-CQDs exhibited high oxidase-like catalytic behavior, which could convert transparent 3,3',5,5'-tetramethylbenzidine (TMB) into blue ox-TMB by dissolved oxygen. After adding ascorbic acid to the Co-CQDs/TMB system, the blue color of the solution faded due to the reduction of blue ox-TMB to colorless TMB. Based on this phenomenon, the Co-CQDs were capable of detecting AA (10-400 μM) with the LOD of 0.27 μM. The fluorometric and colorimetric assays based on the Co-CQDs for the AA detection were then successfully applied in fresh fruits. Furthermore, the high biocompatibility of the Co-CQDs against HeLa cells was verified by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. Thus, the Co-CQDs could be used as a powerful tool for the detection of AA in real samples through a dual-mode method.

1T-phase transition-metal dichalcogenides (TMDs) nanomaterials are one type of emerging and promising near-infrared II (NIR-II) photothermal agents (PTAs) derived from their distinct metallic electronic structure, but it is still challenging to synthesize these nanomaterials. Herein, PdTe 2 nanoparticles (PTNs) with a 1T crystal symmetry and around 50 nm in size are prepared by an electrochemical exfoliation method, and the corresponding photothermal performances irradiated under a NIR-II laser have been explored. The encapsulation of 1,2-distearoyl- sn -glycero-3-phosphoethanolamine-poly(ethylene glycol) (DSPE-PEG) endows PTNs with water solubility, enhanced photothermal stability, and high biocompatibility. Notably, PTN/DSPE-PEG displays a potent absorbance through the NIR-II zone and considerable photothermal conversion efficiency, which is up to 68% when irradiated with a 1060 nm laser. With these unique photothermal properties, excellent in vitro and in vivo tumor inhibition effects of PTN/DSPE-PEG have been achieved under the irradiation of a NIR-II (1060 nm) laser without visible toxicity to normal tissues, suggesting that it is an efficient NIR-II photothermal nanoagent.

A facile and general coordination-precipitation method is developed to synthesize insoluble metal Roussin's black salts (Me-RBSs) as a new type of NIR-responsive NORMs. The weak-field ligand coordination of metal + -RBS - brings a NIR absorption effect of Me-RBSs, and further gives rise to the NIR adsorption-dependent NIR-responsive NO release profile. Intratumoral NIR-responsive release of NO effectively inhibits the growth and metastasis of the metastatic breast cancer. Aqueous insolubility of Me-RBSs ensures lower cytotoxicity and higher thermostability compared with traditional soluble RBSs. This work establishes a new class of NIR-sensitive NO donors, and may spark new inspiration for designing intelligent gas-releasing molecules.