Copper(II) Perfluorinated Carboxylate Complexes with Small Aliphatic Amines as Universal Precursors for Nanomaterial Fabrication

Abstract

Copper(II) carboxylate compounds with ethylamine and isopropylamine of the general formula [Cu2(RNH2)2(µ-O2CRf)4], where R = Et, iPr, and Rf = CnF2n+1, n = 1–6, were characterised in the condensed and gas phases by electron impact mass spectrometry (EI MS), IR spectroscopy, and thermal analysis. A mass spectra analysis confirmed the presence of metallated species in the gas phase. Among the observed fragments, the pseudomolecular ions [Cu2(RNH2)2(µ-O2CRf)3]+ were found, which suggests the dimeric structure of the studied complexes with axially N-coordinated ethyl- or isopropylamine molecules and bridging perfluorinated carboxylates. TGA studies demonstrated that copper transfer to the gas phase occurs even under atmospheric pressure. The temperature range of the [Cu2(RNH2)2(µ-O2CRf)4] and other copper carriers detection, observed in variable temperature infrared spectra, depends on the type of amine. The possible mechanisms of the decomposition of the tested compounds are proposed. The copper films were produced without additional reducing agents despite using Cu(II) CVD precursors in the chemical vapor deposition experiments. The layers of the gel-like complexes were fabricated in both spin- and dip-coating experiments, resulting in copper or copper oxide materials when heated. Dinuclear copper(II) carboxylate complexes with ethyl- and isopropylamine [Cu2(RNH2)2(µ-O2CRf)4] can be applied for the formation of metal or metal oxide materials, also in the nanoscale, by vapour and ‘wet’ deposition methods.

Pivalate complexes of copper(ii) with aliphatic amines as potential precursors for depositing nanomaterials from the gas phase

“…The temperature of the decomposition process onset changed between 313 K and 322 K (T i ), while the temperature of the final product formation was from 540 K to 550 K (T f ). The aforementioned ranges of T i and T f are narrow, in contrast to the previously described complexes with perfluorinated carboxylates: 19,20 TEM diffraction patterns and EDX spectra for the residues revealed that the decomposition product is metallic copper for the complexes (1-4). In the case of the compound (5), with a tertiary amine, a mixture of copper(I) and (II) oxides was identified (Fig.…”

“…The aforementioned ranges of T i and T f are narrow, in contrast to the previously described complexes with perfluorinated carboxylates: [Cu 2 ( t BuNH 2 ) 2 (μ-O 2 CR f ) 4 ], [Cu 2 ( i PrNH 2 ) 2 (μ-O 2 CR f ) 4 ], and [Cu 2 (EtNH 2 ) 2 (μ-O 2 CR f ) 4 ] (R f = CF 3 , C 2 F 5 , C 3 F 7 , C 4 F 9 ). 19,20…”

“…We decided to investigate copper( ii ) compounds with pivalate (2,2-dimethylpropanoate) and amines because our previous studies on complexes with perfluorinated carboxylates and small aliphatic amines [Cu 2 (RNH 2 ) 2 (μ-O 2 CR f ) 4 ], where R = t Bu, i Pr, Et; R f = C n F 2 n +1 , n = 1–6 have indicated that the introduction of a secondary amine ligand improves volatility and causes that they are a good source of metals in the gas phase. 19,20 Moreover, the compounds [Cu 2 (RNH 2 ) 2 (μ-O 2 CC 2 F 5 ) 4 ], where R = t Bu, s Bu, Et and [Cu 2 (EtNH 2 ) 2 (μ-O 2 CC 3 F 7 ) 4 ], have been studied in terms of low-energy electron–molecule interactions for their possible application in the FEBID method. 21,22 Generally, the number of copper( ii ) compounds with non-fluorinated carboxylate and various amines are described.…”

“…Therefore, we would like to test whether non-fluorinated complexes, where a bulky tert -Butyl substituent should increase the volatility of the compounds, can be an alternative to the fluorinated analogues. 19–22…”

Синтез, Кристалічна Структура, Спектральні Характеристики Та Аналіз Поверхні Хіршфельда Комплексів Купруму(ii) З Карбоксилатами, 3,5-Диметил-1h-Піразолом

“…Research on metal carboxylates has always been due to their important roles not only in synthetic chemistry, with the essence of the labile coordination modes of the carboxylate group, with architectures of open and porous frameworks [1][2], but also with regard to biological activities [3-4] and physiological effects [5][6]. The carboxylate groups can adopt a wide range of bonding modes, including monodentate, symmetric and asymmetric chelating, and bidentate and monodentate bridging [7][8][9][10][11].…”