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© The Royal Society of Chemistry. A variety of carbon materials such as carbon nanotubes and graphene have been widely investigated as conductive substrates to immobilize metal complex-based catalysts for electrocatalytic CO2 reduction. However, highly ordered mesoporous carbons have received scant attention as substrates for CO2 reduction electrocatalysts. The unique porous structure of such carbon provides the opportunity to not only house catalytically active materials but also facilitate reactant transport. In this work, we propose a simple approach for immobilization of the highly active and cost-efficient molecular catalyst iron porphyrin, into a highly ordered mesoporous carbon, CMK-3 having a large surface area of 1345 m2 g-1via a simple vacuum infiltration method. The resulting heterogeneous electrocatalyst (CMK-FeTPP) is utilized for the conversion of aqueous CO2 into CO with 92.1% faradaic efficiency and a high effective turnover frequency of 3.9 s-1 at an overpotential of 680 mV. We believe that this new approach has the potential to be widely used to fabricate efficient electrocatalysts for not only CO2 conversion but also other electrochemical gas conversion systems.

© 2020 Wiley-VCH GmbH Novel conductive polymer-based metal complexes were electrochemically synthesized and characterized in relation to (spectro)electrochemical stimuli. Particularly, we focused our attention on terthiophenes functionalized with terpyridine groups, along with Fe2+ cations present during electrochemical synthesis. The resultant electroactive films are coherent, robust, and exhibit mixed absorption profiles upon electrochemical doping, characteristic for both polyterthiophenes and metal-ligand transitions. At certain oxidation potentials, the formation of radical cation and also dication states were observed. The latter, influence the optical transitions related to metal centers, and can reversibly be everted by switching to lower potentials. Furthermore, the polymer “cross-linking metal” can be removed from the structure, which we obtained by partial exchange of Fe2+ with Cu2+ and Zn2+ cations. The conducted cation exchange studies however elucidate the complexity and difficulty of such an approach. With future electropolymerization “strategies” we are expecting to extend film stability during application of relatively high potentials, as well as in the interim of cation exchange.

© 2020 Wiley-VCH GmbH Thermoelectrochemical cells (thermocells) designed for harvesting human body heat can provide constant power output for wearable electronics, supplementing state-of-the-art flexible power storage and conversion solutions. However, a systematic investigation into the optimization of wearable thermocells is lacking, especially with regard to device design, n-type electrolytes, and electrode/electrolyte integration. Here, a n-type gel electrolyte: polyvinyl alcohol-FeCl2/3 with outstanding flexibility and elasticity and exceptional electrolyte/electrode integration into a 3D porous poly(3,4-ethylenedioxythiophene)/polystyrenesulfonate (PEDOT/PSS) electrode, is produced via an in situ chemical crosslinking method. The integrated n-type cell shows excellent seebeck coefficients (0.85 mV K−1) and output current density (1.74 A m−2 K−1) that are comparable with an optimized p-type cell consisting of a carboxymethylcellulose-K3/4Fe(CN)6 electrolyte with a 3D PEDOT/PSS-edge functionalized graphene/carbon nanotube electrode (−1.22 mV K−1 and 1.85 A m−2 K−1). The equivalent performance of the n-type and p-type cells enables the effective series connection of up to 18 pairs of p–n cells that combines to give an output voltage of 0.34 V (∆T = 10 K). This in-series device is fabricated into a proof-of-concept watch strap, which can harvest body heat, charge supercapacitor (up to 470 mF) as well as illuminate a green light emitting diode, demonstrating the practical applications.