Hazardous waste generation in nanomanufacturing is raising serious environmental concerns and increasing the demand for energy and resources for emission control. Although the vapor-phase deposition of nanoscale coatings possesses a solvent-free advantage, recycling precursors from the complex composition in the exhaust is still formidable. Here, a visible-light-driven chemical vapor deposition method is proposed, which allows initiator-free polymer deposition with facile monomer recovery. The photocatalytic radical generation is confined at the monomer/semiconductor interface, maintaining unreacted monomers intact under 420 nm irradiation. Multilayer monomer adsorption conditions are also employed to inhibit the desorption of radical species. Thereby, high-purity monomer can be recycled from the exhaust by condensation with an outstanding recovery rate of 96.28%. Furthermore, this deposition method is demonstrated for synthesizing effective anticorrosion coatings and fabricating self-aligned patterns with an area selectivity of 97.4%. This work provides insights for guiding the design of eco-friendly deposition methods and paves the way to sustainable nanomanufacturing.
Mengjia Cen,Jiawei Wang,Jianxun Liu,Huilin He,Ke Li,Wenfeng Cai,Tun Cao,Yan Jun Liu
Chiral metasurfaces can exhibit a strong circular dichroism, but it is limited by the complicated fabrication procedure and alignment errors. Here, a new type of self-aligned suspended chiral bilayer metasurface with only one-step electron beam lithography exposure is demonstrated. A significant optical chirality of 221° µm −1 can be realized using suspended metasurfaces with a thickness of 100 nm. Furthermore, this study experimentally demonstrates that such a structure is capable of label-free discrimination of the chiral molecules at zeptomole level, exhibiting a much higher sensitivity (orders of magnitude) compared to the conventional circular dichroism spectroscopy. The fundamental principles for chiral sensing using molecules–metasurfaces interactions are explored. Benefiting from the giant chiroptical response, the proposed metadevice may offer promising applications for ultrathin circular polarizers, chiral molecular detectors, and asymmetry information processing.
危险品化学品经营许可证（带存储）