A pre-organised and halogen-free ZnO precursor is used to deposit GZO coatings via aerosol-assisted CVD with properties that exceed industrial standards for low-E coatings and photovoltaics.

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The solid-state structures of all members in the series of trichalcogenaferrocenophanes [FeIJC 5 H 4 E) 2 E′] (E, E′ = S, Se, Te) (1-9) have been explored to understand the trends in secondary bonding interactions (SBIs) between chalcogen elements sulfur, selenium, and tellurium. To complete the series, the crystal structures of the four hitherto unknown complexes [Fe(C 5 H 4 S) 2 Te] (3), [Fe(C 5 H 4 Se) 2 S] (4), [Fe(C 5 H 4 Se) 2 Te] (6), and [Fe(C 5 H 4 Te) 2 S] (7) have been determined in this contribution. The packings of all complexes 1-9 were considered by DFT calculations at the PBE0/pob-TZVP level of theory using periodic boundary conditions. The intermolecular close contacts were considered by QTAIM and NBO analyses. The isomorphous complexes [Fe(C 5 H 4 S) 2 S] (1), [Fe(C 5 H 4 S) 2 Se] (2), and [Fe(C 5 H 4 Se) 2 Se] (5a) form dimers via weak interactions between the central chalcogen atoms of the two trichalcogena chains of adjacent complexes. In the second isomorphous series consisting of [Fe(C 5 H 4 Se) 2 S] (4) and 5b, the complexes are linked together into continuous chains by short contacts via the terminal selenium atoms. The intermolecular chalcogen-chalcogen interactions are significantly stronger in complexes [Fe(C 5 H 4 S) 2 Te] (3), [Fe(C 5 H 4 Se) 2 Te] (6), and [Fe(C 5 H 4 Te) 2 E′] (E′ = S, Se, Te) (7-9), which contain tellurium. The NBO comparison of donor-acceptor interactions in the lattices of [Fe(C 5 H 4 S) 2 S] (1), [Fe(C 5 H 4 Se) 2 Se] (5a and 5b), and [Fe(C 5 H 4 Te) 2 Te] (9) indeed shows that the n(5p Te) 2 → σ*(Te-Te) interactions in 9 are the strongest. All other interaction energies are significantly smaller even in the case of tellurium. The computed natural charges of the chalcogen atoms indicate that electrostatic effects strengthen the attractive interactions in the case of all chalcogen atoms.

Germanium is listed as a critical raw material, and for environmental and economic sustainability reasons, strategies for lower consumption must be implemented. A promising approach is Ge lift‐off concepts, which enable to re‐use the substrate multiple times. Our concept is based on the Ge‐on‐Nothing approach that is the controlled restructuring at high temperature of a macroporous Ge surface, forming a Ge foil weakly attached to its parent wafer. Its suitability as III–V epitaxy seed and support substrate has previously been demonstrated with proof‐of‐concept solar cells. This work focuses on bringing this concept to the next level, by upscaling the detachable area to a full 200‐mm wafer scale, increasing foil thickness for sufficient light absorption in the Ge bottom cell, and improving the control on the strength that is bonding the suspended foil to its parent. By introducing a new high growth‐rate epitaxy process from GeCl4, and by engineering the GeON structure to introduce pillars with ad hoc density and shape, we fabricated P‐type foils with tunable boron doping up to 15 μm in thickness and 11 cm × 11 cm in area, for which the detachment strength could be adapted to the stresses induced by the solar cell process steps. The surface roughness and the electrical and crystal qualities of these foils were inspected by AFM, SIMS, SRP, ECCI, and TEM to check the GeCl4‐based epitaxy conditions and to check that the ad hoc pillars were not introducing any damage. Small‐area triple‐junction lattice‐matched GaInP/GaInAs/Ge solar cells were fabricated on 7‐μm‐thick Ge foils with various pillar densities and on a standard reference Ge wafer. The III–V layer nucleation was virtually the same on both substrates and the solar cells on the GeON foils performed in the same way as the cells on the Ge wafer, albeit a small loss in short‐circuit current and open‐circuit voltage that can be attributed to the thickness reduction and absence of rear‐side passivation. We conclude that it is possible to gain control on the GeON detachability and upscale the concept to areas relevant for the space PV industry, proving that porous germanium is a serious candidate for replacement of bulk Ge wafers in view of a more sustainable multijunction solar cell process.

Fe-doped TiSe2 thin-films were synthesized via low pressure chemical vapor deposition (LPCVD) of a single source precursor: [Fe(η5-C5H4Se)2Ti(η5-C5H5)2]2 (1).