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High-air humidity, especially condensation into droplets under the influence of temperature, can pose a serious threat to air purification filters. This report introduces the use of methyltrimethoxysilane (MTMS) for the silanization hydrophobic modification of cellulose nanofibers (CNFs) and obtains an air filter with super-hydrophobicity (CA = 152.4°) and high-efficiency filtration of particulate matter (PM) through the freeze-drying technology. The antihumidity performance of CNFs filters that undergo hydrophobic modification in high-humidity air is improved. Especially in the case of high-humidity air forming condensed water droplets, the increase in the rate of filtration resistance of the hydrophobically modified CNFs filter is much lower than that of the unmodified filter. In addition, the water-vapor-transmission rate of the hydrophobically modified filter is improved. More importantly, adding MTMS can regulate the porous structure of CNFs filters and improve the filtration performance. The specific surface area and the porosity of the filter are 26.54 m2/g and 99.21%, respectively, and the filtering effects of PM1.0 and PM2.5 reach 99.31 and 99.75%, respectively, while a low-filtration resistance (42 Pa) and a quality factor of up to 0.122 Pa–1 are achieved. This work has improved the application potential of high-performance air-purification devices to remove particulate pollution and may provide useful insights to design next-generation air filters suitable for application in high-air humidity.

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Excellent triboelectric charge density and hydrophobicity are achieved on cellulose nanofibrils (CNFs) by employing a simple and environmentally friendly approach to aminosilane modification of a CNF film. The positive charges on the CNF surface obtain gigantic enhancement, and a CNF-based triboelectric nanogenerator (TENG) with enhanced performance and moisture resistance is prepared. The performance of this functional CNF-based TENG can show outstanding output stability when the environmental humidity is 70%. Meanwhile, this TENG can respond to a variety of human activities, including pressing, stretching, bending, and twisting, indicating outstanding flexibility, and it can still be used to monitor the state of human movement in a human sweat environment. This work is expected to provide more insights and possibilities for application of such a functional CNF-based TENG in self-powered wearable electronics.

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Using clean and sustainable stochastic energy from the environment to eliminate pollution caused by gaseous aldehydes would be an effective strategy to achieve the sustainable development of energy and preserve the environment. Here, a piston-based triboelectric nanogenerator (P-TENG) was used to enhance gaseous acetaldehyde absorption and photocatalytic degradation. An external electric field could be generated on a conductive substrate by the P-TENG, converting wind energy into electricity. This made it possible to efficiently degrade gaseous acetaldehyde in the photocatalytic system. Driven by a light breeze (3.0 m/s), the acetaldehyde removal rate of the system reached 63% within 30 min. The presence of an external electric field could generate more hydroxyl radicals (•OH), superoxide radicals (•O2 –), and holes (h+), which has a positive effect on the photocatalytic degradation of acetaldehyde. The design and concept of this study not only realized the efficient conversion of renewable and sustainable random energy but also could be applied to the efficient removal of gaseous aldehydes, providing an effective way to create a cleaner environment.

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