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The development of hybrid materials with multiple uses by an eco-friendly method is becoming paramount in the field of materials science. The vapor-phase polymerization being an easy, cheap and environmentally friendly method is used to prepare cellulosepolypyrrole (Cell-PPy) hybrid membranes. These hybrid membranes are further deposited with silver nanoparticles through a UV-assisted photoreduction process (Cell-PPy-Ag). The hybrid membranes have been characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA), which reveals a consistent homogenous polymerization of pyrrole on the surface of the cellulose paper filter. The conductivity behaviors of the Cell-PPy (doped and undoped) and Cell-PPy-Ag hybrid membranes have also been investigated, and the obtained results reflect good conducting properties that can be utilized for the development of flexible electrochemical sensors and other biomedical applications. Furthermore, we investigated the antibacterial nature of the Cell-PPy- Ag hybrid membranes with both gram-negative and gram-positive bacteria, Escherichia coli and Staphylococcus aureus, respectively. In this research, we present a simple, eco-friendly, and cost-effective means of mass-producing dual-functional Cell-PPy-Ag membranes with conductivity and antibacterial property. [ABSTRACT FROM AUTHOR]

A photothermal particle (S-PPY) for direct solar evaporation was developed by depositing polypyrrole (PPY) on elemental sulfur (S) via solvent-free vapor phase polymerization. The S-PPY-coated membrane showed an excellent evaporation rate (2.13 kg m-2h−1 at 1 Sun) and potential for water purification and desalination. [Display omitted] • Sulfur (S) particles are nanocoated with polypyrrole (PPY) via solvent-free vapor phase polymerization. • PPY-coated S (S-PPY) are utilized as a photothermal material for solar steam generation. • S-PPY has excellent steam generation performance with evaporation rate of 2.13 Kg m-2h−1 at 1 Sun. • Seawater is desalinated and wastewater is purified through steam generation using S-PPY. The use of solar heat to produce steam holds great potential in terms of solving drinkable freshwater scarcity worldwide. However, the fabrication of low-cost, large-scale photothermal materials remains difficult; existing multi-step processes use toxic solvents. Here, a solvent-free and facile synthetic process is presented: we coat sulfur (S) with polypyrrole (PPY), then use PPY-coated S (S-PPY) as a photothermal layer for solar steam generation. We demonstrate an excellent solar steam evaporation rate (2.13 kg m-2h−1 at 1 Sun light intensity; efficiency 88.92 %). The use of inexpensive and abundant S as a substrate for PPY photothermal composites will find many energy-conversion applications as welll as water purification and desalination via solar steam generation. [ABSTRACT FROM AUTHOR]

In this study, commercially available cellulose membranes were hybridized with conjugated polymer via vapor-phase polymerization using pyrrole and iron chloride as a monomer and oxidant, respectively. The iron ( III) chloride layer dip-coated on the hydrophilic cellulose surface oxidized the vaporized pyrrole monomer leading to the polypyrrole-cellulose hybrid membrane. The conductivity of hybrid membrane was optimized by varying the oxidant concentration and the monomer vapor exposure time. The various surface characterizations of polypyrrole-cellulose hybrid membrane show that the conductive polypyrrole layer was uniformly deposited onto the surface of cellulose fibrous networks unlike the polypyrrole-nylon hybrid membrane prepared in the similar way. The polypyrrole-incorporated cellulose networks exhibits steeper electrical conductance increase over the vertical pressure than its nylon counterpart. Our result suggests that the polypyrrole-cellulose hybrid membrane can be applicable for a disposable high-load pressure sensor. [ABSTRACT FROM AUTHOR]

Solar energy-based steam generation holds immense potential to tackle the problem of 1.1 billion people lacking access to freshwater and 2.7 billion experiencing freshwater scarcity at least one month a year. Efficient, portable, and universal photothermal materials are required for popularity of solar-driven evaporation systems. Herein, a facile one-pot process based on solution-processed vapor phase polymerization is adopted to fabricate polypyrrole-coated cellulose nanocrystals (CNC-PPy). The CNC-PPy dispersed in water is used as an ink (CNC-PPy ink) to create photothermal layers. The developed ink is readily laminated on diverse substrates utilizing a common paintbrush that firmly attached without any delamination after drying. The optimized cellulose membrane (6 coating cycles) presents an excellent evaporation rate of 1.96 Kg m−2 h−1 with corresponding light-to-vapor efficiency of 88.92 % at 1 sun. In addition, the CNC-PPy display excellent antibacterial and antifouling properties in powder and laminated forms against E. coli and S. aureus. Photothermal ink was formed by coating polypyrrole (PPy) on cellulose nanocrystals (CNCs). The CNC-PPy ink has displayed stable lamination on various substrates. The ink coated cellulose membrane showed evaporation rate of 1.96 Kg m−2 h−1 at 1 sun with excellent antibacterial and antifouling properties. [Display omitted] [ABSTRACT FROM AUTHOR]

• Development on vapor phase polymerization via wet-on-wet (WOW-VPP) method to coat conducting polymers. • WOW-VPP is used to coat polypyrrole on never-dried CNCs in aqueous phase. • The process is applicable on water dispersed oxidant immobilized nano-materials. • The process is bulk polymerization free and applied at ambient conditions. Vapor-phase polymerization (VPP) of polypyrrole (PPy) is a versatile and simple form of surface restraint polymerization onto a variety of substrates; only the polymerization initiator (an oxidant) is adsorbed onto the surface. However, traditional VPP features substrate (film, foam and fabric) impregnation/coating with an oxidant, followed by short drying to evaporate excess solvent, and then pyrrole polymerization onto the oxidant coated surface with controlled relative humidity. When seeking to coat PPy on water dispersed nano-materials such as never-dried nanocellulose and chitosan nanoparticles, in-situ chemical oxidative polymerization is most often used. However, bulk polymerization and impurity formation hinder application of the technique to wet substrates. Here, we develop an aqueous wet-on-wet vapor-phase polymerization (WOW-VPP) technique to apply restraint PPy coatings onto wet substrates. Never-dried cellulose nanocrystals (CNCs) served as the model material; we formed PPy-nanocoated hybrids (CNC-PPy), which were then transformed into a lightweight aerogel serving as a compression strain sensor. The sensor evidenced good performance under repeated compression cycles as well as resistivity changes under various applied loads. For proof-of-concept, we used WOW-VPP to coat other wet substrates including polyvinyl alcohol (PVA). The WOW-VPP approach to fabrication of PPy nanohybrids is not associated with bulk polymerization, and is performed at room temperature ambient pressure, renewable and sustainable. Furthermore, the process is solution-processed, simple, and amenable to scale-up. [ABSTRACT FROM AUTHOR]