From the comparison between various films with different composition (polyethylene (PE) and polyamide (PA) layers together with a photocatalytic layer), number of layers, thickness and TiO2 concentration, it was concluded that for all the samples the light absorption was linearly correlated to TiO2 surface density.
Optical pathlength changes (op = φλ/(4π)) in the sample are induced by light absorption of oxy- and deoxy-hemoglobin in blood, where φ is measured phase change at a specific depth and λ = 1328 nm is central wavelength of the DWP-OCT system.
The results revealed that the CdS/K2La2Ti3O10 samples displayed a strong light absorption in the visible region, and the UV vis diffuse reflectance spectra changed with the proportion of CdS present.
Meanwhile, the other Au NIs film-incorporated samples showed the similar light absorption spectra.
The samples were analyzed by light absorption wavelength scan between 500 nm and 600 nm in a GBC-920 spectrophotometer (GBC, Australia).
To exclude the interference of the turbidity of lipids upon light absorption, samples were diluted 1 5 in PBS and centrifuged (10,000 × g, 1 h, 4°C).
Therefore, the light absorption of sample ALD is as high as 98%, which may result from synergistic band structure of the heterogeneous materials, the light trapping effect for the hierarchical architecture, and the smooth transition of refractive index from air (n = 1) through ZnO branches (n = 2.0) to Si backbones (n = 3.5).
Corrected intensity functions of light absorption with sample, I ex(λ sam), were also determined from excitation spectra of the system (450 480 nm, scan rate 60 nm/min), whereas the corrected intensity function of the emission was determined from emission spectra (I em, 550 800 nm, scan rate 60 nm/min).Quantum yield was calculated from the equation as follows [45, 46]: (2).
The photocurrent density of the photoelectrode varies with the different growth concentrations of ZnSO4 aqueous solution, which may be related to the resistance and surface-to-volume ratio of the samples that could affect the light absorption.
This further increases the overall light absorption of the sample due to the change in topography.
Zirconium mono-doped NTA sample also presents no obviously visible light absorption.
