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Abstract: SiO2 films have been prepared on sapphire by radio frequency magnetron reactive sputtering in order to increase the optical and mechanical properties of infrared windows and domes of sapphire at elevated temperatures. Infrared transmission and flexural strength of uncoated and coated sapphires have been investigated at different temperatures. SiO2 films were shown to have apparent antireflective effect on sapphire substrate at room temperature. With increasing temperature, the coated sapphires have larger average transmission than the uncoated ones. The temperature was proven to only weakly affect the absorption coefficient and antireflection capability of the deposited films. It is also indicated that the flexural strengths of the c-axis sapphire samples coated with SiO2 films are increased by 1.2 and 1.5 times than those of uncoated at 600 and 800°C, respectively. [Copyright &y& Elsevier]

[Display omitted] • Redox active surface-attached MOFs (SURMOFs) bearing pendant ferrocene (Fc) groups are grown on self-assembled monolayers (SAMs) functionalized surfaces by layer-by-layer (LBL) deposition method. • Two SAMs, 4-mercaptopyridine and 6-mercaptopurine, are used for the growth of redox active SURMOFs, and the nature of SAMs significantly affects the morphology and redox activity of deposited Fc-SURMOFs. • An electron hopping mechanism for the charge transport in redox active Fc-SURMOFs is proposed based on detailed electrochemical studies. As electroactive metal–organic frameworks (MOFs) become the centerpiece of many emerging applications in electrocatalysis, energy storage/conversion and electronics, the ability to grow high-quality of electroactive MOF thin films and understanding the mechanism of charge transport in the frameworks are crucial. Herein, we demonstrate that the use of ferrocene pendant biphenyl dicarboxylate (bpdc-Fc) ligand allows the successful growth of redox-active surface-attached MOFs (SURMOFs) [Cu 2 (bpdc-Fc) 2 dabco] SURMOF, on self-assembled monolayers (SAMs) functionalized surfaces by layer-by-layer (LBL) deposition method. The nature of the SAMs significantly affects the morphologies and electrochemical properties of [Cu 2 (bpdc-Fc) 2 dabco] SURMOFs owing to their different ability to coordinate Cu 2 dimmer. The purine-based SAMs offer excellent anchoring sites for the nucleation of MOF crystals leading to dense films with good electrochemical properties. On the contrary, sparse MOF nanocrystals with poor electrochemical properties were obtained on pyridine-based SAMs. A redox hopping mechanism accompanied by anion diffusion was proposed to explain the different redox properties of [Cu 2 (bpdc-Fc) 2 dabco] SURMOFs on SAMs. This work has potential to contribute to rational design and growth of novel MOFs for the applications in ionic conductors, electrocatalysts, energy storage devices and electrochemical sensors. [ABSTRACT FROM AUTHOR]