Sequential infiltration synthesis

Sequential infiltration synthesis (SIS) is a technique derived from <a href="/facts/Atomic_layer_deposition/NWFrQIHC">atomic layer deposition</a> (ALD) in which a <a href="/facts/Polymer/eF32E50K">polymer</a> is infused with <a href="/facts/Inorganic_compound/TfFfzxSz">inorganic</a> material using <a href="/facts/Sequential/gV2S4uqp">sequential</a>, self-limiting exposures to <a href="/facts/Gas/hVVAoodV">gaseous</a> precursors, enabling precise manipulation over the composition, structure, and properties. The technique has applications in fields such as nanotechnology, materials science, and electronics, where precise material engineering is required. 
This <a href="/facts/Chemical_synthesis/3KXsVVwC">synthesis</a> uses <a href="/facts/Metal-organic_compound/WFv2Ypum">metal-organic</a> vapor-phase precursors and co-reactants that dissolve and diffuse into <a href="/facts/Polymer/eF32E50K">polymers</a>. These precursors interact with the <a href="/facts/Functional_group/GXkSPsjM">functional groups</a> of the polymers through reversible complex formation or irreversible <a href="/facts/Chemical_reaction/GpqWlKrz">chemical reactions</a>, resulting in <a href="/facts/Composite_material/UBysQldh">composite materials</a> that can exhibit <a href="/facts/Nanostructure/rkeQGqt7">nano-structured</a> properties. The metal-organic precursor (A) and co-reactant vapor (B) are supplied in an alternating ABAB sequence. Following SIS, the organic phase may be removed thermally or chemically to leave only the inorganic components behind. This approach facilitates the fabrication of materials with controlled properties such as <a href="/facts/Chemical_composition/vjo4uMQ0">composition</a>, <a href="/facts/Stoichiometry/I5p9cJzV">stylometric</a>, <a href="/facts/Porosity/UoyAJU8X">porosity</a>, <a href="/facts/Electrical_resistivity_and_conductivity/akyCKvMy">conductivity</a>, <a href="/facts/Refractive_index/yjkzvgeE">refractive index</a>, and <a href="/facts/Functionality_(chemistry)/AbW0mHPE">chemical functionality</a> on the <a href="/facts/Nanoscale/hyFgwMKM">nano-scale</a>. 
SIS has been utilized in fields, including <a href="/facts/Electronics/E4JhgISq">electronics</a>, <a href="/facts/Energy_storage/9GWtAPeb">energy storage</a>, <a href="/facts/Artificial_intelligence/lJGauQwX">AI</a>, and <a href="/facts/Catalysis/LPBS7TQC">catalysis</a>, for its ability to modify material properties. SIS is sometimes referred to as "multiple pulsed <a href="/facts/Vapour_phase_decomposition/rnBrNpbv">vapor-phase</a> <a href="/facts/Infiltration_(hydrology)/p4n7qhVy">infiltration</a>" (MPI), "vapor phase infiltration" (VPI) or "sequential vapor infiltration" (SVI).
SIS involves the 3D distribution of functional groups in <a href="/facts/Polymer/eF32E50K">polymers</a>, while its predecessor, ALD, is associated with the <a href="/facts/Two-dimensional_space/f4b397W8">two-dimensional</a> distribution of reactive sites on solid surfaces. In SIS, the partial pressures and exposure times for the precursor pulse are typically larger compared to ALD to ensure adequate infiltration of the precursor into the three-dimensional polymer volume through dissolution and <a href="/facts/Diffusion/KbAxroBa">diffusion</a>. The process relies on the diffusive transport of precursors within polymers, with the resulting distribution influenced by <a href="/facts/Time/HceJKUGB">time</a>, <a href="/facts/Pressure/eyc37GRG">pressure</a>, <a href="/facts/Temperature/QyGe4gmj">temperature</a>, <a href="/facts/Polymer_chemistry/wdfr6fs4">polymer chemistry</a>, and <a href="/facts/Microstructure/dVGy1kq2">micro-structure</a>.

Sequential infiltration synthesis open-in-new

Sequential infiltration synthesis