title: Nongassing long-lasting electro-osmotic pump with polyaniline-wrapped aminated graphene electrodes.
abstract: An efficient nongassing electro-osmotic pump (EOP) with long-lasting electrodes and exceptionally stable operation is developed by using novel flow-through polyaniline (PANI)-wrapped aminated graphene (NH2-G) electrodes. The NH2-G/PANI electrode combines the excellent oxidation/reduction capacity of PANI with the exceptional conductivity and inertness of NH2-G. The flow rate varies linearly with voltage but is highly dependent on the electrode composition. The flow rates at a potential of 5 V for pristine NH2-G and PANI electrodes are 71 and 100 μL min(-1) cm(-2), respectively, which increase substantially by the use of NH2-G/PANI electrode. It increased from 125 to 182 μL min(-1) cm(-2) as the fraction of aniline increased from 66.63 to 90.90%. The maximum flux obtained is 40 μL min(-1) V(-1) cm(-2) with NH2-G/PANI-90.9 electrodes. The assembled EOP remained exceptionally stable until the electrode columbic capacity was fully utilized. The prototype shown here delivered 8.0 μL/min at a constant applied voltage of 2 V for over 7 h of continuous operation. The best EOP produces a maximum stall pressure of 3.5 kPa at 3 V. These characteristics make it suitable for a variety of microfluidic/device applications.
authors.affiliation: Department of Chemical Engineering, Indian Institute of Technology , Kanpur 208016, India.
authors.forename: Rudra
authors.initials: R
authors.lastname: Kumar
authors.forename: Kousar
authors.initials: K
authors.lastname: Jahan
authors.forename: Rajaram K
authors.initials: RK
authors.lastname: Nagarale
authors.forename: Ashutosh
authors.initials: A
authors.lastname: Sharma
mesh_terms: D000814:Aniline Compounds / Q000737:chemistry*; D002384:Catalysis; D004563:Electrochemistry / Q000379:methods*; D004566:Electrodes; D006108:Graphite / Q000737:chemistry*; D008567:Membranes, Artificial; D044085:Microfluidics / Q000379:methods; D018625:Microscopy, Atomic Force; D008855:Microscopy, Electron, Scanning; D008956:Models, Chemical; D009995:Osmosis; D010087:Oxides / Q000737:chemistry; D011208:Powders; D011312:Pressure; D012822:Silicon Dioxide / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D014961:X-Ray Diffraction
chemical_list: D000814:Aniline Compounds; D008567:Membranes, Artificial; D010087:Oxides; D011208:Powders; C416807:polyaniline; D012822:Silicon Dioxide; D006108:Graphite; C023650:aniline
keywords: electro-osmotic pump; functionalized graphene; microfluidics; polyaniline; silica membrane