RESUMEN
By tailoring the coordination sphere of vanadium to accommodate a 7-coordinate geometry, a highly soluble (>1.3 M) and reducing (-1.2 V vs Ag/AgCl) flow battery electrolyte is generated from [V(DTPA)]2-/3- (DTPA = diethylenetriaminepentaacetate). Bulk spectroelectrochemistry is performed in situ to assess material properties in both oxidized and reduced states. Flow batteries are assembled in near neutral pH conditions and operated with discharge energy densities of 12.5 Wh L-1 and high efficiency. Further, the first chelated flow battery using the same aminopolycarboxylate ligand for both electrolytes is generated. The presented batteries demonstrate comparable performance to the iron-vanadium and all-vanadium flow batteries while doubling the effective discharge energy of vanadium (Wh per mol V) and minimizing safety and operating risks, offering grid-scale energy storage alternatives.
RESUMEN
Delamination of the electron-transporting polymer N2200 from indium tin oxide (ITO) in aqueous electrolytes is mitigated by modifying ITO with an azide-functionalized phosphonic acid (PA) which, upon UV irradiation, reacts with the polymer. The optical, electrochemical, and spectroelectrochemical properties of N2200 thin films are retained in aqueous and non-aqueous media.
RESUMEN
Polymer semiconductors are fascinating materials that could enable delivery of chemical fuels from water and sunlight, offering several potential advantages over their inorganic counterparts. These include extensive synthetic tunability of optoelectronic and redox properties and unique opportunities to tailor catalytic sites via chemical control over the nanoenvironment. Added to this is proven functionality of polymer semiconductors in solar cells, low-cost processability, and potential for large-area scalability. Herein we discuss recent progress on soft photoelectrochemical systems and define three critical knowledge gaps that must be closed for these materials to reach their full potential. We must (1) understand the influence of electrolyte penetration on photoinduced charge separation, transport, and recombination, (2) learn to exploit the swollen polymer/electrolyte interphase to drive selective fuel formation, and (3) establish co-design criteria for soft materials that sustain function in the face of harsh chemical challenges. Achieving these formidable goals would enable tailorable systems for driving photoelectrochemical fuel production at scale.