On the protonation of oxo- and hydroxo-groups of the goethite (α-FeOOH) surface: A FTIR spectroscopic investigation of surface O–H stretching vibrations

Elementary Reactions in Polynuclear Ions and Aqueous?mineral Interfaces: A New Geology

“…These frequencies were used to build a valence force field for borate and boric acid, which was then used to calculate the vibrational partition functions for both ions, and, hence, K 34 , yielding a value of 1.019 (in other words, boric acid is enriched in 11 B relative to borate under equilibrium conditions). This approach was used to infer more acidic ocean pH values (pH<7.5) 20 million years in the geologic past.…”

A novel reusable nanocomposite: FeOOH/CBC and its adsorptive property for methyl orange

“…As a p-type semiconductor with a band gap of 2.12 eV, FeOOH is one of the most stable iron oxide under ambient conditions [24]. It can be synthesized by a facile method [25][26][27][28][29][30][31] and easy to be coupled with other components because of its numerous surface hydroxyl groups [32,33]. However, FeOOH nanoparticles are apt to agglomerate due to nanometer size effect, decreasing the adsorption activity.…”

Quantification of Moisture Contents in Iron and Manganese Ores

“…-The first region up to about 150°C is named moisture, hydroscopic moisture, surface water, onset of bulk and surface dehydration, non-stoichiometric hydroxyl units (excess water), surface adsorbed water, chemisorbed surface water and adsorbed water; 2,7,8,10,[12][13][14][15] -The second region goes up to about 200-230°C, depending on the sample characteristics (particle size, morphology, synthetic or natural, etc.) and is named as bulk dehydration and surface dehydration/dehydroxylation, nonstoichiometric water from bulk and surface, weakly bound OH groups, surface-bound and bulk-sequestered water, loosely bound hydroxyl units, dehydration from hydrogenbonded water or dehydroxylation of surface; 6,[14][15][16][17] -The third region comprises the transformation of goethite into hematite, which is completed below 400°C.…”

“…and is named as bulk dehydration and surface dehydration/dehydroxylation, nonstoichiometric water from bulk and surface, weakly bound OH groups, surface-bound and bulk-sequestered water, loosely bound hydroxyl units, dehydration from hydrogenbonded water or dehydroxylation of surface; 6,[14][15][16][17] -The third region comprises the transformation of goethite into hematite, which is completed below 400°C. This loss of mass has been termed as structural hydroxyl, bulk dehydroxylation, intrinsic dehydroxylation, dehydroxylation, non-stoichiometric hydroxyl units, strongly bounded water and OH groups; 2,6,10,12,[14][15][16][17] This variety of names arises from the fact that the goethite surface is highly reactive, owing to the presence of terminal OH groups.…”

“…14,18,19) The hydrogen bonding can occur with singly-coordinated, doubly-coordinate and triply-coordinate oxygens, resulting in different bond lengths for the several configurations. Thus, it is reasonable to anticipate that the removal of water from the surface of goethite will be a multi-stage process, each one requiring a different temperature.…”