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811.
Spherical domes are created on the surface of polycarbonate samples, and microvoids are formed within the bulk using only a femtosecond oscillator with pulse energy of just 0.47?nJ. Size of spherical domes and shape of microvoids are controlled by changing the laser focus inside the material. Their formation is explained by a combination of heat accumulation and dome formation dynamics, where the dome acts as a microlens shifting the laser focus within the sample. The technique described here provides a simple avenue for fabricating smooth microlens arrays of various sizes and opens the possibility for direct fabrication of complex three-dimensional microfluidic channels in transparent materials. 相似文献
812.
Reaction of [Ni(1,5-cod)2] (30 equiv.) with PEt3 (46 equiv.) and S8 (1.9 equiv.) in toluene, followed by heating at 115 °C for 16 h, results in the formation of the atomically precise nanocluster (APNC), [Ni30S16(PEt3)11] (1), in 14% isolated yield. Complex 1 represents the largest open-shell Ni APNC yet isolated. In the solid state, 1 features a compact “metal-like” core indicative of a high degree of Ni–Ni bonding. Additionally, SQUID magnetometry suggests that 1 possesses a manifold of closely-spaced electronic states near the HOMO–LUMO gap. In situ monitoring by ESI-MS and 31P{1H} NMR spectroscopy reveal that 1 forms via the intermediacy of smaller APNCs, including [Ni8S5(PEt3)7] and [Ni26S14(PEt3)10] (2). The latter APNC was also characterized by X-ray crystallography and features a nearly identical core structure to that found in 1. This work demonstrates that large APNCs with a high degree of metal–metal bonding are isolable for nickel, and not just the noble metals.The atomically-precise nanocluster, [Ni30S16(PEt3)11], features a compact “metal-like” core indicative of a high degree of Ni–Ni bonding, along with an open-shell ground state. 相似文献
813.
Michael Wilms Lesly V. Melendez Dr. Rohan J. Hudson Dr. Christopher R. Hall Samantha Prabath Ratnayake Prof. Dr. Trevor Smith Prof. Dr. Enrico Della Gaspera Prof. Dr. Gary Bryant Dr. Timothy U. Connell Prof. Dr. Daniel E. Gómez 《Angewandte Chemie (International ed. in English)》2023,62(24):e202303501
We report a new composite material consisting of silver nanoparticles decorated with three-dimensional molecular organic cages based on light-absorbing porphyrins. The porphyrin cages serve to both stabilize the particles and allow diffusion and trapping of small molecules close to the metallic surface. Combining these two photoactive components results in a Fano-resonant interaction between the porphyrin Soret band and the nanoparticle-localised surface-plasmon resonance. Time-resolved spectroscopy revealed the silver nanoparticles transfer up to 37 % of their excited-state energy to the stabilising layer of porphyrin cages. These unusual photophysics cause a 2-fold current increase in photoelectrochemical water-splitting measurements. The composite structure provides a compelling proof of concept for advanced photosensitiser systems with intrinsic porosity for photocatalytic and sensing applications. 相似文献
814.