The fabrication of 3D ink-printed and sintered porous Si scaffolds as electrode material for lithium-ion batteries is explored. A hierarchically-porous architecture consisting of channels (~220 μm in diameter) between microporous Si struts is created to accommodate the large volume change from Si (de)lithiation during electrochemical (dis)charging. The influence of sintering parameters on Si strut porosity and the resulting mechanical and electrochemical properties of the scaffolds are studied experimentally and computationally. Varying sintering temperatures (1150–1300 °C) and sintering times (1–16 h) the open porosity within the Si filaments can be tailored between 46 and 60%. Pore size (3–6 μm) and wall…
Using 3D printing to manufacture shape memory polymers (SMPs) becomes popular, since the technique endows SMPs the ability to shape into desired structures according to their applications. Among various types of SMPs, epoxy-based shape memory polymer and their composites are known for their high modulus and strength. However, limited by their rheological behavior, it is still hard to prepare high-quality printable epoxy materials. Here, by carefully tuning of rheological properties, we can prepare printable ink showing good shape retention, excellent mechanical performances below and above the glass transition temperature of epoxy, as well as good shape memory effect. The prepared…
Thermal management is of importance to microelectronic industry. Owing to both excellent thermal conduction and electrical insulation, hexagonal boron nitride (BN) platelets are the widely-used thermal conductive fillers in polymers. Adding high content of BN can endow polymers high thermal conductivity, but in most cases, destroy the flexibility, failure strength as well as processability of the polymers significantly. Here, we report a multi-material 3D printing technique to prepare high thermal conductive epoxy based composites, by which BN platelets were assembled together in heat-conducting phase to form the dense, continuous thermal pathway. The BN platelets show excellent alignment along printing direction…