High throughput investigation of an emergent and naturally abundant 2D material: Clinochlore

[Display omitted] •A complete description of clinochlore 2D structure and fundamental properties by its 3D bulk form;•Identification of impurities with detailed analysis, showing their nanoscale distribution that reveals homogeneous incorporation of Cr and Mn, but the formation of iron inclusions. We have also investigated the impurity impact on clinochlore optoelectronic properties both experimental and theoretically;•Demonstration that bandgap and fundamental properties seem to be mildly affected as the thickness approaches to a single clinochlore layer, as probed by SINS in few-layer flakes, preserving the most relevant properties of the bulk material. Phyllosilicate minerals, which form a class of naturally occurring layered materials (LMs), have been recently considered as a low-cost source of two-dimensional (2D) materials. Clinochlore [Mg5Al(AlSi3)O10(OH)8] is one of the most abundant phyllosilicate minerals in nature, exhibiting the capability to be mechanically exfoliated down to a few layers. An important characteristic of clinochlore is the natural occurrence of defects and impurities which can strongly affect their optoelectronic properties, possibly in technologically interesting ways. In the present work, we carry out a thorough investigation of the clinochlore structure on both bulk and 2D exfoliated forms, discussing its optical features and the influence of the insertion of impurities on its macroscopic properties. Several experimental techniques are employed, followed by theoretical first-principles calculations considering several types of naturally-ocurring transition metal impurities in the mineral lattice and their effect on electronic and optical properties. We demonstrate the existence of requirements concerning surface quality and insulating properties of clinochlore that are mandatory for its suitable application in nanoelectronic devices. The results presented in this work provide important informations for clinochlore potential applications and establish a basis for further works that intend to optimize its properties to relevant 2D technological applications through defect engineering.