An elegant and precise method to fabricate asymmetrical structures and/or gradient structures was developed based on a vapor-phase sublimation and deposition process. The fabricated materials exhibited versatility and had advantages such as well-controlled pore structures and functional properties ranging from an asymmetrical distribution to a gradient hierarchy; precisely addressed interface chemistries and properties for the constructed materials; and flexibility to produce the materials at multiple scales. By using a time-dependent customization parameter to control the bulk size and/or the dispersion of molecules, fabrication of the materials was demonstrated, producing particles with hierarchical pore structures and with bulk sizes ranging from >500 μm to submicrons, as well as gradients with both continuously varied porosity and chemical functionality that were demonstrated to be in a controlled direction and varied across multiple scales (centimeter, millimeter, and micrometer). By exploiting chemical vapor deposition to enable multicomponent copolymerization during the fabrication process, multifunctional poly-p-xylylenes formed building blocks for these hierarchical materials and provided the defined surface chemistries. The proposed functional hierarchical materials were constructed and assembled in the vapor phase and in one step, and prospective materials produced by this method are expected to have novel properties and unlimited applications.

A variety of crystalline colloid binary halide, ternary perovskite-like and ternary perovskite-derivative nanostructures with well-defined morphologies were synthesized, thus expanding materials chemistry to the new category of nanomaterials. The optical and photocatalytic properties of ternary nanostructures were investigated.

Surface modification layers are performed on the surfaces of biomaterials and have exhibited promise for decoupling original surface properties from bulk materials and enabling customized and advanced functional properties. The physical stability and the biological compatibility of these modified layers are equally important to ensure minimized delamination, debris, leaching of molecules, and other problems that are related to the failure of the modification layers and thus can provide a long-term success for the uses of these modified layers. A proven surface modification tool of the functionalized poly-para-xylylene (PPX) system was used as an example, and in addition to the demonstration of their chemical conjugation capabilities and the functional properties that have been well-documented, in the present report, we additionally devised the characterization protocols to examine stability properties, including thermostability and adhesive strength, as well as the biocompatibility, including cell viability and the immunological responses, for the modified PPX layers. The results suggested a durable coating stability for PPXs and firmly attached biomolecules under these stability and compatibility tests. The durable and stable modification layers accompanied by the native properties of the PPXs showed high cell viability against fibroblast cells and macrophages (MΦs), and the resulting immunological activities created by the MΦs exhibited excellent compatibility with non-activated immunological responses and no indication of inflammation.