Surface engineering of nanoparticles for highly efficient UV‐shielding composites

Abstract

Overexposure to ultraviolet (UV) with high energy can not only hurt human skin but also accelerate the degradation of organic matter. Hence, the preparation of polymer‐based UV‐shielding nanocomposites has attracted substantial attention due to the low cost, easy processing and wide applications. Notably, the highly efficient UV‐shielding polymer nanocomposites are still hindered by the agglomeration of inorganic anti‐UV nanoparticles (Nps) in polymer matrix and the narrow absorption range of UV‐shielding agents. To overcome the aforementioned bottlenecks, surface engineering of anti‐UV Nps including organic modification and inorganic hybridization has been extensively employed to enhance the UV‐shielding efficiency of composites. Herein, to deliver the readers a comprehensive understanding of the surface engineering of anti‐UV Nps, we systematically summarize the recent advances in surface organic modification and inorganic hybridization related to anti‐UV Nps. The UV‐shielding mechanism and the factors affecting UV‐shielding efficiency of polymer nanocomposites are also discussed. Finally, perspectives on remaining challenges and future development of highly efficient UV‐shielding composites are outlined.

Assembly of AIEgen‐Based Fluorescent Metal–Organic Framework Nanosheets and Seaweed Cellulose Nanofibrils for Humidity Sensing and UV‐Shielding

“…The optical transparency and UV-shielding capability of nanocomposites are quite beneficial for wearable and optical devices. [21] The UV-vis transmittance spectra of the TOCNF-MOF composite films manifested their high optical transparency with transmittance of ca. 90% in the visible wavelength range from 400 to 800 nm, similar to that for the neat TOCNF film.…”

“…The UV blocking factor value of the composite film with 4.0 wt% of MOF nanosheets was 189, indicating its excellent UV protective ability as compared to the recently reported cellulose-based nanocomposite films (Table S2, Supporting Information). [21,22] The excellent UV-shielding capacity of TOCNF-MOF composite film was also demonstrated by using a fluorescent pattern, which exhibited obvious fluorescence under UV light (365 nm) irradiation when a neat TOCNF film was applied. In contrast, the fluorescence emission of the pattern could not be observed as the UV light was shielded by the TOCNF-MOF composite film (Figure 5b).…”

Nanotechnology in the Olympic Winter Games and Beyond

“…Therefore, it is essential to add an anti-UV layer to ski goggles to offer additional protection from UV light. Nanoparticles of inorganic semiconductors are one major type of anti-UV material (Figure a), due to their appropriate bandgap, good stability, low toxicity, low cost, and small size that give little scattering of visible light . For example, ZnO nanoparticles have a band gap of 3.37 eV and thus can absorb radiations with wavelengths shorter than 368 nm, covering almost the whole UV region (Figure c). , …”

“…Nanoparticles of inorganic semiconductors are one major type of anti-UV material (Figure 4a), due to their appropriate bandgap, good stability, low toxicity, low cost, and small size that give little scattering of visible light. 18 For example, ZnO nanoparticles have a band gap of 3.37 eV and thus can absorb radiations with wavelengths shorter than 368 nm, covering almost the whole UV region (Figure 4c). 15,19 Fogging is also a serious problem because small water droplets of the fog can scatter light and decrease the transparency of ski goggles.…”

Effects of chemically functionalized TiO2 nanoparticles on the UV‐shielding characteristics of polymer‐dispersed liquid crystals

“…Usually, inorganic nanoparticles (NPs), especially metal oxides with wide bandgap (e.g., >3 eV), such as TiO 2 , ZnO and CeO 2 , are often used to improve the UV-shielding properties of composites. [24][25][26][27] However, due to their high specific surface area, inorganic NPs tend to form agglomerates in the polymer matrix, which will not only weaken the UV-shielding efficiency of the polymer composites, but also affect the optical transparency of the composites. In…”