Highly sensitive surface-enhanced Raman scattering (SERS) detection was achieved on plasmon-free TiO2 photonic artificial microarray, which can be quickly recovered under simulated solar light irradiation and repeatedly used. The sensitive detection performance is attributed to the enhanced matter-light interaction through repeated and multiple light scattering in photonic microarray. Moreover, the SERS sensitivity is unprecedentedly found to be dependent on the different light-coupling performance of microarray with various photonic band gaps, where microarray with band gap center near to laser wavelength shows a lower SERS signal due to depressed light propagation, while those with band gap edges near to laser wavelength show higher sensitivity due to slow light effect.

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Yolk-shell (Y-S) structured Fe3O4@void@CdS nanoparticles (NPs) are synthesized through a one-pot coating-etching process with Fe3O4@SiO2 as the core, where the coating of an outer CdS shell from a chemical bath deposition (CBD) process is simultaneously accompanied by the gradual etching of an inner SiO2 shell. The as-prepared Fe3O4@void@CdS NPs (ca. 200 nm) possess good monodispersity and a uniform CdS shell of ca.15 nm. This composite exhibits excellent photo-Fenton (ph-F) activity toward the degradation of methylene blue (MB) in a wide pH working range of 4.5-11 under the visible light irradiation. A series of control experiments demonstrate the unique Y-S structure contributes to the enhanced activity, where the separation of hole-electron pair from CdS and the reduction of Fe(2+) from Fe(3+) are mutually promoted. The similar efficiency can also be achieved when the shell component changes to TiO2 or CeO2, demonstrating a general strategy for the design of robust ph-F agent.

A facile self-assembly synthetic procedure was exploited to fabricate mesoporous-silica-capped Fe 3 O 4 mesoporous clusters, so-called bimodal mesoporous Fe 3 O 4 @SiO 2 composites. Structural characterization demonstrated that the core of the Fe 3 O 4 clusters is coated with a mesoporous silica shell of uniform size distribution. Moreover, unprecedentedly good tunability of the core size (180-1700 nm) and the shell thickness (20-75 nm) is achievable by changing the synthetic parameters. Application of the composite in the removal of the or- [a] Key

Hierarchical macro-mesoporous silica materials co-incorporated with Cr and Ti 12(MM-Si-Cr-Ti) were directly synthesized by adopting close-packed array of polystyrene 13 microsphere as hard template for macropore through a simple soaking-calcination way, where 14 the Si/Ti ratio was fixed at 200 and Si/Cr ratio varied from 200-10. Ti specie is highly dispersed 15 in the porous matrix and Cr specie mainly existes as tetra-coordinated CrO3 when Si/Cr≧50, and 16 transformed to a mixture of CrO3 and crystallized hexa-coordinated Cr2O3 as determined by 17 wide-angle XRD patterns, raman, EPR spectra and UV-Vis diffuse reflectance spectra. This 1 highly interconnected porous material co-incorporated with Cr and Ti presented visible-light 2 driven photocatalytic activity towards the degradation of AO7, which can be optimized by 3 simply tuning Cr content in the precursor solution. The superiority of hierarchical macro-4 mesoporous structure of MM-Si-Cr-Ti over macroporous Si-Cr-Ti oxide (Ma-Si-Cr-Ti) and 5 mesopores (Me-Si-Cr-Ti) for the photocatalytic application was illustrated by a comparative 6 study. The visible light responsive activity is attributed to the effective metal to metal charge 7 transfer from Cr (VI) to Ti (IV), which is benefitted from the uniform dispersion of these two 8 species in the hierarchical porous matrix. 9