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A series of fluorenyl and trifluoromethyl groups containing co-poly(ether imide)s (S-co-PIs) have been prepared from a new diamine monomer; 9,9-bis(3-methoxy-4-(4-amino(3-trifluoro-methyl)biphenoxy)phenyl)-9H-fluorene (APHPF). The polymers were prepared by the polycondensation reaction of 1,4,5,8-naphthalenetetracarboxylic dianhydride (NTDA) with two different diamines; APHPF and 4,4′-diaminostilbene-2,2′-disulfonicacid (DSDSA) as a co-monomer. The monomer and polymers were well characterized by 1 H NMR and ATR-FTIR spectroscopies. The co-polymers were soluble in various organic solvents and membranes were prepared from solution cast route. The S-co-PIs showed high thermal and mechanical stability. TEM and AFM results supports the formation of phase separated morphology with well separated ionic-clusters. All these S-co-PIs displayed reasonably high proton conductivity. One of the copolymers (DAN-80; IECw ∼2.27 meq g −1 ) exhibited a proton conductivity as high as 149 mS cm −1 which was comparable to that of Nafion® 117 (165 mS cm −1 ) at 80 °C. The co-polymers maintain a good balance between water-uptake and swelling ratios and peroxide resistance. Microbial Fuel Cell (MFC) performance of the co-polymers were evaluated DAN-80 exhibited a similar performance like Nafion® 117 under similar test condition.

The present work deals with a frugal paper-based microbial fuel cell (PMFC) that generates an average power of 25 μW per device using Shewanella putrefaciens. Bacteria colonized on the paper matrix can be activated by readily available nutrient sources leading to instant power generation. Current study translates this technology to energize a wireless Internet of Things (IoT) sensor. A well-designed stacking of multiple cells is adopted to boost the power output. The power profile characteristics of three 10-unit PMFC configurations namely series (C1), parallel (C2), and combination of both (C3) are investigated. Attempts to directly charge a supercapacitor using serially-connected PMFC stack results in voltage reversal (VR). Hence, to harvest this microbial energy prudently, a customized power management system consisting of integrated Maximum Power Point Tracking (MPPT) feature is deployed. This helps in interfacing the PMFCs to capture charge, boost the harvested voltage and to prevent voltage reversal (VR). Power harvested from PMFCs is stored into a supercapacitor in order to drive the wireless IoT sensor module, which in turn measures temperature and communicates the data to a smart phone. The current endeavours can pave the way for “bacteria powered IoT devices” by unlocking the potential of microbes through PMFCs.