New Y type chromophores were synthesized and the hyperpolarizability can be effectively translated into large electro-optic coefficients in poled polymers.

In this brief review, nonlinear optical (NLO) chromophores widely used in electro-optic (EO) devices are summarized according to their EO coefficients. The advances of EO modulators based on organic materials in high bandwidth and low half wave voltages (V p ) are discussed. The review is mainly devoted to the following aspects: (1) verification of high frequency operation and reduction of V p for all polymer waveguide EO modulators; (2) structures and advantages of sol-gel waveguide EO modulators; (3) principles and developments of silicon-organic hybrid (SOH) EO modulators. All the considerations are illustrated by the architecture of the devices and the used physical and chemical principles are explained in detail. Further means of improvement of their parameters are indicated.

The selective two-electron O2 reduction reaction (2e− ORR) represents a green, mild, and on-site means of synthesizing of H2O2. However, its practical feasibility depends on the development of advanced electrocatalysts,...

Four second-order nonlinear optical chromophores with D–π–A, D–A–π–A and D–D–π–A architectures have been synthesized and systematically characterized.

No abstract

The analysis of dried drop patterns has various applications in research fields like archeology, medical practice, printing, and so on. In this paper, we studied the evaporation and pattern formation of polytetrafluoroethylene (PTFE) colloid droplets on smooth substrate and rough substrates with different roughness. We found that the evaporation of droplets shows remarkable coffee-ring effect on smooth substrate and that the cross-section of the ring is wedge-shaped with its thickness decreasing from the edge to the center. However, with increasing roughness, the effect strengthened, with the section of the coffee-ring changing from wedge- to hill-shaped. The contact angle decreased with increasing roughness, leading to an increase in evaporation rate. Moreover, wicking led to additional evaporation, which also enhanced capillary flow, moving more particles to the edge. In addition, the rough structure of the substrate inhibited the back-flow of the capillary flow, preventing the particles’ move to the center. The formation of radial wrinkles on the edge also led to particle retention, preventing them from moving to the center. All these factors contribute to the decreased width and increased height of the coffee-ring pattern after evaporation on rough surfaces. It is an effective method to regulate the deposition pattern of evaporating droplet by changing the substrate roughness.

Self-assembled binary multichromophore dendrimers HDSD–FDSD have been developed to increase the poling efficiency, refractive Index and stability of the EO materials.

New chromophores containing a novel pyrrole-based bridge were synthesized and the hyperpolarizability can be effectively translated into large electro-optic coefficients in poled polymers.