RESUMO
Flexible hydroelectric generators (HEGs) are promising self-powered devices that spontaneously derive electrical power from moisture. However, achieving the desired compatibility between a continuous operating voltage and superior current density remains a significant challenge. Herein, a textile-based van der Waals heterostructure is rationally designed between conductive 1T phase tungsten disulfide@carbonized silk (1T-WS2@CSilk) and carbon black@cotton (CB@Cotton) fabrics with an asymmetric distribution of oxygen-containing functional groups, which enhances the proton concentration gradients toward high-performance wearable HEGs. The vertically staggered 1T-WS2 nanosheet arrays on the CSilk fabric provide abundant hydrophilic nanochannels for rapid carrier transport. Furthermore, the moisture-induced primary battery formed between the active aluminum (Al) electrode and the conductive textiles introduces the desired electric field to facilitate charge separation and compensate for the decreased streaming potential. These devices exhibit a power density of 21.6 µW cm-2, an open-circuit voltage (Voc) of 0.65 V sustained for over 10 000 s, and a current density of 0.17 mA cm-2. This performance makes them capable of supplying power to commercial electronics and human respiratory monitoring. This study presents a promising strategy for the refined design of wearable electronics.
RESUMO
Flexible moisture-electric generators (MEGs) capture chemical energy from atmospheric moisture for sustainable electricity, gaining attention in wearable electronics. However, challenges persist in the large-scale integration and miniaturization of MEGs for long-term, high-power output. Herein, a vertical heterogeneous phase-engineering MoS2 nanosheet structure based silk and cotton were rationally designed and successfully applied to construct wearable MEGs for moisture-energy conversion. The prepared METs exhibit â¼0.8 V open-circuit voltage, â¼0.27 mA/cm2 current density for >10 h, and >36.12 µW/cm2 peak output power density, 3 orders higher than current standards. And the large-scale device realizes a current output of 0.145 A. An internal phase gradient between the 2H semiconductor MoS2 in carbonized silks and 1T metallic MoS2 in cotton fibers enables a phase-engineering-based heterogeneous electric double layer functioning as an equivalent parallel circuit, leading to enhanced high-power output. Owing to their facile customization for seamless adaptation to the human body, we envision exciting possibilities for these wearable METs as integrated self-power sources, enabling real-time monitoring of physiological parameters in wearable electronics.
RESUMO
DNA cytosine methylation plays a vital role in repressing retrotransposons, and such derepression is linked with developmental failure, tumorigenesis and aging. DNA methylation patterns are formed by precisely regulated actions of DNA methylation writers (DNA methyltransferases) and erasers (TET, ten-eleven translocation dioxygenases). However, the mechanisms underlying target-specific oxidation of 5mC by TET dioxygenases remain largely unexplored. Here we show that a large low-complexity domain (LCD), located in the catalytic part of Tet enzymes, negatively regulates the dioxygenase activity. Recombinant Tet3 lacking LCD is shown to be hyperactive in converting 5mC into oxidized species in vitro. Endogenous expression of the hyperactive Tet3 mutant in mouse oocytes results in genome-wide 5mC oxidation. Notably, the occurrence of aberrant 5mC oxidation correlates with a consequent loss of the repressive histone mark H3K9me3 at ERVK retrotransposons. The erosion of both 5mC and H3K9me3 causes ERVK derepression along with upregulation of their neighboring genes, potentially leading to the impairment of oocyte development. These findings suggest that Tet dioxygenases use an intrinsic auto-regulatory mechanism to tightly regulate their enzymatic activity, thus achieving spatiotemporal specificity of methylome reprogramming, and highlight the importance of methylome integrity for development.