Search

Self‐charging power systems (SCPSs) are envisioned as promising solutions for emerging electronics to mitigate the increasing global concern about battery waste. However, present SCPSs suffer from large form factors, unscalable fabrication, and material complexity. Herein, a type of highly stable, eco‐friendly conductive inks based on poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) are developed for direct ink writing of multiple components in the SCPSs, including electrodes for miniaturized spacer‐free triboelectric nanogenerators (TENGs) and microsupercapacitors (MSCs), and interconnects. The principle of "one ink, multiple functions" enables to almost fully print the entire SCPSs on the same paper substrate in a monolithic manner without post‐integration. The monolithic fabrication significantly improves the upscaling capability for manufacturing and reduces the form factor of the entire SCPSs (a small footprint area of ≈2 cm × 3 cm and thickness of ≈1 mm). After pressing/releasing the TENGs for ≈79000 cycles, the 3‐cell series‐connected MSC array can be charged to 1.6 V while the 6‐cell array to 3.0 V. On‐paper SCPSs are promising to serve as lightweight, thin, sustainable, and low‐cost power supplies. [ABSTRACT FROM AUTHOR]

Molybdenum (Mo)‐based nanozymes have been attracting increasingly extensive attention in photocatalytic antitumor field due to their versatile physicochemical properties, whereas the limited light capture rate and high recombination rate of photogenerated carriers seriously impedes their further development. Herein, MoO3‐starring silica nanozymes with hyaluronic acid modification (HMMSNs@HA) are innovated by hydrogenation to simultaneously achieve oxygen vacancies (OVs) engineering and tumor adaptive accumulation for the second near‐infrared (NIR‐II, 1064 nm) light‐potentiated thermal‐catalytic therapy. The hydrogenation‐regulated OVs can narrow the band gap of HMMSNs from 2.66 to 1.16 eV, achieving optimal optical absorption in NIR‐II region. Additionally, HMMSNs hold high separation efficacy of electron‐hole pairs to facilitate the generation of reactive oxygen species under laser irradiation. Significantly, HMMSNs@HA are stable in tumor microenvironment, while can degrade in normal physiological conditions, thereby offering tumor‐adaptive accumulation. Synchrotron radiation‐based extended X‐ray absorption fine structure spectroscopy reveals that OVs enabling the Mo4+ and Mo5+ formation, which can react with tumor endogenous H2O2 to produce hydroxyl radicals. Furthermore, OVs‐induced localized surface plasmon resonance effect endows the nanozymes with photothermal conversion efficacy of 32.3%, which affords NIR‐II‐excited photonic hyperthermia‐enhances catalytic therapy. All the experimental results demonstrate the high safety and superiorities of HMMSNs@HA for NIR‐II‐initiate therapy. [ABSTRACT FROM AUTHOR]

Single‐atom nanozymes (SAzymes) can effectively mimic the metal active centers of natural enzymes at the atomic level owing to their atomically dispersed active sites, thereby maximizing atom utilization efficiency and density of active sites. Hence, SAzymes can be considered the most promising candidates to replace natural enzymes. Herein, a PEGylated mesoporous Mn‐based single‐atom nanozyme (PmMn/SAE) employing a coordination‐assisted polymerization pyrolysis strategy that uses polydopamine for photothermal‐augmented nanocatalytic therapy is designed. PmMn/SAE exhibits excellent multiple enzymatic performance, including catalase‐like, oxidase‐like, and peroxidase (POD)‐like performance, due to the atomically dispersed Mn active species. As a result, PmMn/SAE not only catalyzes the decomposition of endogenous H2O2 to generate O2 for relieving hypoxia inside the tumor but also transfers electrons to O2 to produce superoxide radicals to kill tumor cells. Meanwhile, PmMn/SAE is able to trigger Fenton‐like reactions to generate highly toxic hydroxyl radicals to induce cancer cell apoptosis. The POD‐like catalytic mechanism of mMn/SAE is revealed using experimental results and density functional theory. Furthermor, PmMn/SAE shows good photothermal conversion efficiency (η = 22.1%) in the second near‐infrared region (1064 nm). Both the in vitro and in vivo experimental results indicate that PmMn/SAE can effectively kill cancer cells through photothermal‐enhanced catalytic therapy. [ABSTRACT FROM AUTHOR]