Pore‐Selective SnS Functionalization in Honeycomb‐Patterned Films by a Breath Figure Process Accompanied by Chemical Reaction

Abstract

A new fabrication process for the pore‐selective functionalization of honeycomb‐patterned porous (HCP) films is demonstrated by a modified breath figure method accompanied by an in situ chemical reaction. A polymer solution containing one reactant is cast under humid conditions containing counter reactant to facilitate a chemical reaction at condensed droplet/polymer solution interface, which results in the pore‐selective functionalization of HCP films. Polystyrene (PS) solution containing tin(II) chloride is cast under humid conditions containing aqueous hydrogen sulfide for the formation of tin sulfide (SnS)‐functionalized PS HCP films. H2S humidity is generated by pumping ambient air through the aqueous sodium sulfide solution. Scanning electron microscopy, transmission electron microscopy, and elemental mapping analyses indicate the formation of SnS as thin layers selectively in the pores of PS HCP films.

Selective Coating of SnS on the Bio‐Inspired Moth‐Eye Patterned PEDOT:PSS Polymer Films

“…The template film was prepared by following our recent report using reactive BF method . Pore‐selective SnS‐functionalized PS HCP films were fabricated by using a reactive BF process.…”

“…However, it is not easy to fabricate the MEP films with selective coating of functional materials on the film surface using the HCP film as a template due to the difficulty of pore selective functionalization of HCP film and also transferability of the functional materials. However, we have recently reported a new method to obtain pore selectively functionalized HCP film using a modified BF method accompanying a chemical reaction, in which the polymer solution containing a reactant was cast under humid conditions containing its counter reactant for interfacial reaction and pore functionalization …”

Modified Breath Figure Methods for the Pore-Selective Functionalization of Honeycomb-Patterned Porous Polymer Films

“…In the bottom-up process of the BF mechanism, the stage at which there is an interfacial interaction of water droplet and polymer solution can be applied for the site-selective functionalization. Applying this phenomenon, Huh et al recently introduced a modified BF method, called the reactive BF (rBF) method, for the single-step fabrication of pore-selective functionalized films by accompanying an interfacial chemical reaction during the BF process [ 98 , 109 , 110 , 111 , 112 , 113 ]. For this method, a solvent-soluble reactant is added to the hydrophobic polymer solution, and a water-soluble counter reactant is added to the water used for humid conditions.…”

“…For this method, a solvent-soluble reactant is added to the hydrophobic polymer solution, and a water-soluble counter reactant is added to the water used for humid conditions. When the polymer solution containing functionalizing reactant is cast under humid conditions containing counter reactant, a chemical reaction happens at the aqueous droplet/polymer solution interface and the product is formed in the pore of HCP film as a coating, summarized in Table 3 [ 109 , 110 , 111 , 112 ]. The benefit of this approach is that any material, either organic [ 109 , 110 , 111 , 112 ] or inorganic [ 113 ], can be functionalized by this method in one single step.…”

“…When the polymer solution containing functionalizing reactant is cast under humid conditions containing counter reactant, a chemical reaction happens at the aqueous droplet/polymer solution interface and the product is formed in the pore of HCP film as a coating, summarized in Table 3 [ 109 , 110 , 111 , 112 ]. The benefit of this approach is that any material, either organic [ 109 , 110 , 111 , 112 ] or inorganic [ 113 ], can be functionalized by this method in one single step. Male et al fabricated pore functionalized polyaniline (PANI) HCP porous films by in-situ polymerization via the BF method [ 110 ].…”