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No abstract

Photonic crystals incorporating metal nanoparticles have recently attracted increasing interest because they may open a way to generate novel optical properties. Although they provide an opportunity to manipulate combined optical signals, to date, optical properties of these composite materials have been scarcely investigated. Here, we present the first example of gold-nanoparticle-infiltrated polystyrene (GNIPS) inverse opals, which not only preserve localized surface plasmon resonance (LSPR) properties of gold nanoparticles (GNPs), but also replicate photonic features from templates. By varying the refractive index (RI) and the incident angle, the relative shifts between resonance peaks and diffraction peaks are observed. On the basis of the volatilization kinetics of ethanol within the GNIPS films, we investigate the external interactions of LSPR and photonic band gap (PBG). It is found that the LSPR peak of GNPs in GNIPS is unexpectedly red-shifted with the decrease of effective RI. Additionally, due to the reversible change of the two characteristic peaks, these GNIPS films exhibit an optical "on-off switching" capability, which is useful in monitoring the changes of the microenvironment by the permeation and release of surrounding media.

We present here a facile route to the incorporation of gold nanoparticles (GNPs) with desired sizes into three-dimensionally ordered macroporous (3DOM) matrixes. Our route combined the first attachment of small GNPs to the silica colloidal crystal templates as precursors and their subsequent controlled growth by the in-situ chemical reduction method. The desired enlargement of GNPs was acquired via their alternating and repeated exposure to solutions of auric salts and reducing agent NH(3)OH. Such gold-decorated silica templates were also converted into self-sustained polystyrene (PS) macroporous films with GNPs embedded in their wall structures. The growth of gold seeds can be easily followed by their UV-vis absorbance spectra. The route provides an alternative way to incorporate GNPs with predetermined sizes into 3DOM matrixes without destroying their ordered structures. A highlight of our approach is that it obviates the need for the preformation of various-sized GNPs, which is an indispensable step in many other approaches.

The empirical conclusions regarding the influence of innovation on green total factor productivity (GTFP) are relatively mixed. Based on China's provincial panel data from 1999 to 2015, this paper uses the number of patent applications to measure regional innovation capacity, and comprehensively examines the linear and nonlinear effects of innovation on GTFP. Our results show that innovation plays a leading role in promoting GTFP growth in China in general. However, two different types of patents, invention patents and non-invention patents, have heterogeneous impacts on China's green growth under the difference of innovation level. Additionally, the relationship between innovation and China's GTFP also differs significantly before and after 2009. A further nonlinear effect analysis based on a panel threshold model reveals that the impact of innovation on GTFP is higher with the rise of human capital, knowledge stock and financial development.However, only the appropriate environmental regulation stringency is conducive to promoting the influence of innovation on China's green growth. Overall, our findings contribute to a better understanding regarding the impact of innovation on GTFP in China.