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Surface functionalization of inorganic semiconductor substrates, particularly silicon, has focused attention toward many technologically important applications, involving photovoltaic energy, biosensing and catalysis. For such modification processes, oxide-free (H-terminated) silicon surfaces are highly required, and different chemical approaches have been described in the past decades. However, their reactivity is often poor, requiring long reaction times (2-18 h) or the use of UV light (10-30 min). Here, we report a simple and rapid surface functionalization for H-terminated Si(111) surfaces using alkyl silanols. This catalyst-free surface reaction is fast (15 min at room temperature) and can be accelerated with UV light irradiation, reducing the reaction time to 1-2 min. This grafting procedure leads to densely packed organic monolayers that are hydrolytically stable (even up to 30 days at pH 3 or 11) and can display excellent antifouling behavior against a range of organic polymers.

The quest for sustainable and more efficient energy-converting devices has been the focus of researchers&prime, efforts in the past decades. In this study, SiO2 nanofiber mats were fabricated through an electrospinning process and later functionalized using silane chemistry to introduce different polar groups OH (neutral), SO3H (acidic) and NH2 (basic). The modified nanofiber mats were embedded in PBI to fabricate mixed matrix membranes. The incorporation of these nanofiber mats in the PBI matrix showed an improvement in the chemical and thermal stability of the composite membranes. Proton conduction measurements show that PBI composite membranes containing nanofiber mats with basic groups showed higher proton conductivities, reaching values as high as 4 mS&middot, cm&minus, 1 at 200 C.