The new acyclic and potentially heptadentate dinucleating ligand, 2,6-bis(N,N-bis-(2-pyridylmethyl)-sulfonamido)-4-methylphenolato (bpsmp(-)) contains two tertiary sulfonamide groups. The sulfonamide donors permit a greater degree of control over the accessibility of mono versus dinuclear complexes compared to their closely related amine-containing counterparts, on account of their relatively weaker donor properties. A series of air-stable dinuclear complexes of Co(II), Mn(II) and Cu(II) containing two auxiliary acetate ligands have been prepared. The absence of acetate in reaction mixtures containing Co(II) and Mn(II) led to mononuclear complexes, with water ligands completing the coordination spheres of the metal ions, even in the presence of large excess of the metal ions. Thus, bridging acetate ligands appear to stabilise the dinuclear structures for the relatively labile Co(II) and Mn(II) ions. A mononuclear complex of V(IV)=O was isolated even in the presence of acetate, possibly because the oxyl groups on each V(IV) prevent formation of a bis-acetato-bridged complex. Reaction of one equivalent of CuCl(2) with bpsmpH led to isolation of two different mononuclear complexes, dependent on the identity of the solvent. The phenol group is coordinated in only one of these complexes. A dinuclear Cu(II) complex was isolated when two equivalents of the metal salt were used in the reaction.

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A comparison of the electrochemical properties of a series of dinuclear complexes [M(2)(L)(RCO(2))(2)](+) with M = Mn or Co, L = 2,6-bis(N,N-bis-(2-pyridylmethyl)-sulfonamido)-4-methylphenolato (bpsmp(-)) or 2,6-bis(N,N-bis(2-pyridylmethyl)aminomethyl)-4-tert-butylphenolato (bpbp(-)) and R = H, CH(3), CF(3) or 3,4-dimethoxybenzoate demonstrates: (i) The electron-withdrawing sulfonyl groups in the backbone of bpsmp(-) stabilize the [M(2)(bpsmp)(RCO(2))(2)](+) complexes in their M(II)(2) oxidation state compared to their [M(2)(bpbp)(RCO(2))(2)](+) analogues. Manganese complexes are stabilised by approximately 550 mV and cobalt complexes by 650 mV. (ii) The auxiliary bridging carboxylato ligands further attenuate the metal-based redox chemistry. Substitution of two acetato for two trifluoroacetato ligands shifts redox couples by 300-400 mV. Within the working potential window, reversible or quasi-reversible M(II)M(III)↔ M(II)(2) processes range from 0.31 to 1.41 V for the [Co(2)(L)(RCO(2))(2)](+/2+) complexes and from 0.54 to 1.41 V for the [Mn(2)(L)(RCO(2))(2)](+/2+) complexes versus Ag/AgCl for E(M(II)M(III)/M(II)(2)). The extreme limits are defined by the complexes [M(2)(bpbp)(CH(3)CO(2))(2)](+) and [M(2)(bpsmp)(CF(3)CO(2))(2)](+) for both metal ions. Thus, tuning the ligand field in these dinuclear complexes makes possible a range of around 0.9 V and 1.49 V for the one-electron E(M(II)M(III)/M(II)(2)) couple of the Mn and Co complexes, respectively. The second one-electron process, M(II)M(III)↔ M(III)(2) was also observed in some cases. The lowest potential recorded for the E°(M(III)(2)/M(II)M(III)) couple was 0.63 V for [Co(2)(bpbp)(CH(3)CO(2))(2)](2+) and the highest measurable potential was 2.23 V versus Ag/AgCl for [Co(2)(bpsmp)(CF(3)CO(2))(2)](2+).

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Electrolyte supported cells (ESC), with Sc2O3‐stabilized ZrO2 (ScSZ) electrolytes, Gd‐doped ceria (CGO) or M/CGO (M = Ni, Ru) infiltrated Sr0.94Ti0.9Nb0.1O3 (STN94) anodes and LSM/YSZ cathodes, were evaluated for their initial performance and long‐term stability. Power density for the Ru/CGO infiltrated cell reached ∼0.7 W cm–2 at 850 °C, 4% H2O/H2, whereas the Ni/CGO infiltrated cell reached ∼0.3 W cm–2, with the current morphologies and loadings. Operation at 0.125 A cm–2, 850 °C, feeding 50% H2O/H2 to the anode and air to the cathode, for a period >300 h, showed superior stability for the Ru/CGO infiltrated cell, with ∼0.04 mV h–1 degradation rate, when compared to the Ni/CGO infiltrated cell (∼0.5 mV h–1). For the Ni/CGO case, the observed degradation has been tentatively linked to initial changes in the electrochemical active area and long‐term detrimental interactions between components.

The persistent problems with Ni-YSZ cermet based SOFCs, with respect to redox stability and tolerance towards sulfur has stimulated the development of a full ceramic cell based on strontium titanate(ST)-based anodes and anode support materials, within the EU FCH JU project SCOTAS-SOFC. Three different compositions (La, Y and Nb substituted ST) have been developed as anode backbones for either 25 cm 2 or larger than 100 cm 2 cell areas. Cell performances, once infiltrated with suitable electro catalysts, exhibited a maximum power density of 0.5 W/cm 2 at 850 °C. While the ST based backbone remains intact and tolerant to redox cycles, cell performance degradation appears linked to the infiltrated electro catalysts. The materials have also been assessed with respect to their electrical and mechanical properties, in order to further evaluate their potential use as anode and anode support layers in SOFCs.

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