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Despite various applications of alkylzinc carboxylates in chemistry and materials science, the corresponding organozinc derivatives of organophosphorus compounds still represent an insufficiently explored area. To fill this gap, we report on the synthesis of alkylzinc phosphinates and their use as efficient precursors of phosphinate-coated ZnO nanocrystals in the quantum size regime. Examples of a series of alkylzinc phosphinates with the general formula [RZn(O PR' )] (R=tBu or Et) have been prepared through equimolar reactions between ZnR and a selected phosphinic acid, namely dimethylphosphinic acid (dmpha-H), methylphenylphosphinic acid (mppha-H), diphenylphosphinic acid (dppha-H), or bis(4-methoxyphenyl)phosphinic acid (dmppha-H). The reactivities of alkylzinc phosphinate complexes toward H O and O have also been investigated, which resulted in the isolation of two oxo-zinc phosphinate clusters, that is, [Zn (μ -O)(dppha) ] and [Zn (μ -O)(dmppha) ], as well as the unique alkoxy(oxo)zinc cluster [Zn (μ -O)(μ -OtBu)(dppha) ]. Analysis of the crystal structures has revealed that organozinc complexes incorporating phosphinate ligands exhibit a unique capacity for shape-driven self-assembly to produce extended networks, including noncovalent quasi-porous materials. Finally, monodispersed and quantum-sized ZnO NCs coated with phosphinate ligands have been prepared using a non-external-surfactant-assisted wet-chemical organometallic approach based on well-defined [RZn(O PR' )]-type compounds. The resulting brightly luminescent ZnO NCs exhibit average core sizes and hydrodynamic diameters in the ranges 2-4.5 nm and 5-8 nm, respectively. The size of the inorganic core is slightly affected by the character of the incorporated phosphinate ligand, being smallest for ZnO NCs coated by asymmetrically substituted mppha ligands. Regardless of whether or not various phosphinate coating ligands could be controllably applied on the ZnO NC surface, no significant differences were found in the luminescence profiles of the analyzed nanosystems.

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Zinc oxide (ZnO) is a promising electron‐transport layer (ETL) in thin‐film photovoltaics. However, the poor chemical compatibility between commonly used sol–gel‐derived ZnO nanostructures and organo–metal halide perovskites makes it highly challenging to obtain efficient and stable perovskite solar cells (PSCs). Here, a novel approach is reported for low‐temperature processed pure ZnO ETLs for planar heterojunction PSCs based on ZnO quantum dots (QDs) stabilized by dimethyl sulfoxide (DMSO) as easily removable solvent molecules. With no need for the ETL doping or surface modification, the champion PSC comprising the mixed‐cation and mixed‐halide Cs5(MA0.17FA0.83)95Pb(I0.83Br0.17)3 absorber layer reaches a maximum power conversion efficiency of 20.05%, which is significantly higher than that obtained for a reference device based on a standard sol–gel‐derived ZnO nanostructured layer (17.78%). Thus, along with the observed better operational stability in ambient conditions and elevated temperature, the champion device achieves the state‐of‐the‐art performance among reported non‐passivated pure ZnO ETL‐based PSCs. The improved photovoltaic performance is attributed to both a higher uniformity of the surface morphology and a lower defects density of films based on the organometallic‐derived QDs that are likely to ensure the enhanced stability of the ZnO/perovskite interface.

The ability to utilize polluting gases in efficient metal-mediated transformations is one of the most pressing challenges of modernc hemistry.D espite numerous studies on the insertiono fS O 2 into MÀCb onds, the chemical reaction of SO 2 with organozinc compounds remains little explored.T of ill this gap, we report here the systematic study of the reaction of Et 2 Zn towards SO 2 as well as the influence of Lewis bases on the reactionc ourse.W hereas the equimolar reactionp rovided an ovel example of as tructurally characterized organozinc ethylsulfinate compound of general formula [(EtSO 2 )ZnEt] n ,t he utilization of an excesso fS O 2 led to the formation of the zinc(II) bis(ethylsulfinate) compound [(EtSO 2 ) 2 Zn] n .M oreover,w eh ave discovered that the presence of N-donorL ewis basesr epresents an efficient tool for the preparation of extendedz inc ethylsulfinates, whichi n turn led to the formation of 1D [(EtSO 2 ZnEt) 2 (hmta)] n and 2D [((EtSO 2 ) 2 Zn) 2 (DABCO)] n ·solv (in whichs olv = THFo rt oluene, hmta = hexamethylenetetramine, and DABCO = 1,4-diazabicyclo[2.2.2]octane) coordination polymers, respectively.T he results of DFT calculations on the reactivity of SO 2 towards selected ZnÀCr eactive speciesa sw ell as the role of an N-donorL ewis base on the stabilization of the transition states complementthe discussion.Scheme1.Schematicrepresentation of structurally diverse alkylsulfinatesof the general formula RSO 2 M.[a] Dr.