22/09/2014 - Você já ouviu falar do Germaneno? Até hoje, eu nunca tinha ouvido, pois, a novidade é tão recente que nem o Google registra o significado de Germaneno (Germanene, em inglês), um material integrado por uma camada da espessura de apenas um átomo de germânio e que só foi anunciado ao mundo neste mês de setembro de 2014, quando um grupo de cientistas liderados por Guy Le Lay, da Universidade de Aix-Marseille, publicou um artigo especial no New Journal of Physics dando notícia do novo material.
Já falamos aqui em grafeno um material revolucionário formado por camadas finíssimas de apenas um átomo e com propriedades extraordinárias. Outros materiais desse mesmo tipo estão surgindo, entre os quais o Silicieno (de silício) e o Staneno (de estanho), um material teoricamente previsto pelo grupo liderado pelo cientista Prof. Shoucheng Zhang's da Universidade de Stanford, EUA.
A foto aqui publicada é do Grafeno, mas – supostamente – o germaneno é muito parecido, preveem alguns cientistas. Veja abaixo algumas informações adicionais que levantei na Wikipedia, em inglês.
(...) Germanene is a material made up of a single layer of germanium atoms.[1] The material is created in a process similar to that of silicene and graphene, in which high vacuum and high temperature are used to deposit a layer of germanium atoms on a substrate.[1] High-quality thin films of germanene have revealed unusual two-dimensional structures with novel electronic properties suitable for semiconductor device applications and materials science research.In September 2014, G. Le Lay and others reported the deposition of a single atom thickness, ordered and two-dimensional multi-phase film by molecular beam epitaxy upon a gold surface in a crystal lattice with Miller indices (111). The structure was confirmed with scanning tunneling microscopy (STM) revealing a nearly flat honeycomb structure.[2]
We have provided compelling evidence of the birth of nearly flat germanene—a novel, synthetic germanium allotrope which does not exist in nature. It is a new cousin of graphene.
—Guy Le Lay from Aix-Marseille University, New Journal of Physics
(...) Germanene's electronic and optical properties have been determined from ab initio calculations,[13] and structural and electronic properties from first principles.[14] These properties make the material suitable for use in the channel of a high-performance field-effect transistor[15] and have generated discussion regarding the use of elemental monolayers in other electronic devices.[16] The electronic properties of germanene are unusual, and provide a rare opportunity to test the properties of Dirac fermions.[17][18] These unusual properties are generally shared by graphene, silicene, germanene, and stanene.[18]
(...) Stanene[1][2] is a topological insulator, theoretically predicted by Prof. Shoucheng Zhang's group at Stanford, which may display dissipationless currents[clarification needed] at its edges near room temperature. It is composed of tin atoms arranged in a single layer, in a manner similar to graphene.[3] Stanene got its name by combining stannum (the Latin name for tin) with the suffix -ene used by graphene.[4] Research is ongoing in Germany and China, as well as at laboratories at Stanford and UCLA.[5]
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