• Effective intensity distributions used for direct laser interference exposure

      Xu, Jia; Wang, Zuobin; Zhang, Ziang; Wang, Dapeng; Weng, Zhankun; Chinese Academy of Sciences; Changchun University of Science and Technology; University of Bedfordshire (Royal Society of Chemistry, 2015-06-12)
      This paper presents a method to obtain periodic structures with different feature shapes using direct laser interference lithography. In the method, the desired structures are produced by controlling the effective intensity distributions of interference patterns during the exposure process. The effective intensity distributions are adjusted by changing the exposure beam intensity based on the material modification thresholds. In the simulations and experiments, different exposure intensities were used to study the interactions between the effective intensity distributions and the materials, and direct four- and six-beam laser interference lithography systems were set up to pattern silicon wafers. The shapes and sizes of the fabricated surface structures changed with the effective intensities. The experimental results are in accordance with the theoretical models and simulations.
    • Flower-shaped TiO2 clusters for highly efficient photocatalysis

      Ning, Xiao-Hui; Meng, Qing-Ling; Han, Yong-Lu; Zhou, Dong-Yang; Li, Li; Cao, Liang; Weng, Zhankun; Ding, Ran; Wang, Zuobin; Changchun University of Science and Technology (Royal Society of Chemistry, 2017-07-12)
      Titanium dioxide (TiO2) is one of the most widely used semiconductors, with a variety of applications such as water purification, photovoltaic cells, cancer treatment, gas sensors and photocatalysis. Flower-shaped TiO2 clusters can be obtained on patterned fluorine-doped tin oxide (FTO) substrates with one- and two-dimensional (1D and 2D) grating patterns through a two-step process combining laser interference ablation technology with a hydrothermal method. The patterned TiO2 clusters exhibit enhanced photocatalytic degradation of rhodamine B (RhB) and good durability. This work provides a facile route toward the applications of TiO2 clusters in solar-driven clean energy and environmental technologies.
    • Influence of magnetic field on morphological structures and physiological characteristics of bEnd.3 cells cultured on polypyrrole substrates

      Yang, Xue; Ma, Ke; Yang, Libo; Chen, Yujuan; Qu, Yingmin; Wang, Ying; Wang, Xinyue; Yang, Fan; Sun, Qi; Song, Zhengxun; et al. (Royal Society of Chemistry, 2019-12-11)
      This paper employs a spin-coated method to construct conductive polypyrrole (PPy) substrates which present superior properties for controlling the morphological structures and functions of bEnd.3 cells. The PPy substrates with a homogeneous particle size, uniform distribution and proper roughness show enhanced hydrophilic characteristics and improve cell adhesion to the substrates. The changes in the mechanical properties of cells and the responses to the designed substrates and magnetic field are also explored. Due to the synergistic effect between the magnetic field and the conductive PPy substrate, the cells cultured in such an environment exhibit applanate shapes with more branches and enhanced cell viability. In addition, the cells preferentially extend along the magnetic field direction. The mechanical characteristics of cells change significantly under varying magnetic intensity stimulations (5–16 mT). The satisfying effect on cells' morphology and outgrowth is acquired at the magnetic intensities of 9–10 mT and duration of 20 min, compared with other stimulated groups, while retaining cell viability. Moreover, the cells express higher adhesion up to 5.2 nN. The results suggest that the application of the PPy substrates and magnetic field is a promising candidate for the protection of neurovascular units and treatment of neurological diseases.