Zarattini Marco, Dun Chaochao, Isherwood Liam H, Felten Alexandre, Filippi Jonathan, Gordon Madeleine P, Zhang Linfei, Kassem Omar, Song Xiuju, Zhang Wenjing, Ionescu Robert, Wittkopf Jarrid A, Baidak Aliaksandr, Holder Helen, Santoro Carlo, Lavacchi Alessandro, Urban Jeffrey J, Casiraghi Cinzia
Department of Chemistry, University of Manchester Oxford Road Manchester UK M13 9PL
The Molecular Foundry, Lawrence Berkeley National Laboratory Berkeley CA 94720 USA.
J Mater Chem A Mater. 2022 Jun 21;10(26):13884-13894. doi: 10.1039/d1ta06695a. eCollection 2022 Jul 5.
Two-dimensional (2D) anatase titanium dioxide (TiO) is expected to exhibit different properties as compared to anatase nanocrystallites, due to its highly reactive exposed facets. However, access to 2D anatase TiO is limited by the non-layered nature of the bulk crystal, which does not allow use of top-down chemical exfoliation. Large efforts have been dedicated to the growth of 2D anatase TiO with high reactive facets by bottom-up approaches, which relies on the use of harmful chemical reagents. Here, we demonstrate a novel fluorine-free strategy based on topochemical conversion of 2D 1T-TiS for the production of single crystalline 2D anatase TiO, exposing the {001} facet on the top and bottom and {100} at the sides of the nanosheet. The exposure of these faces, with no additional defects or doping, gives rise to a significant activity enhancement in the hydrogen evolution reaction, as compared to commercially available Degussa P25 TiO nanoparticles. Because of the strong potential of TiO in many energy-based applications, our topochemical approach offers a low cost, green and mass scalable route for production of highly crystalline anatase TiO with well controlled and highly reactive exposed facets.
二维（2D）锐钛矿型二氧化钛（TiO₂）由于其具有高反应活性的暴露晶面，预计与锐钛矿纳米微晶相比会表现出不同的性质。然而，块状晶体的非层状性质限制了二维锐钛矿TiO₂的获取，这使得无法使用自上而下的化学剥离方法。人们付出了巨大努力，通过自下而上的方法来生长具有高反应活性晶面的二维锐钛矿TiO₂，这种方法依赖于使用有害化学试剂。在此，我们展示了一种基于二维1T-TiS₂的拓扑化学转化的新型无氟策略，用于生产单晶二维锐钛矿TiO₂，其纳米片的顶部和底部暴露{001}晶面，侧面暴露{100}晶面。与市售的德固赛P25 TiO₂纳米颗粒相比，这些晶面的暴露且无额外缺陷或掺杂，在析氢反应中产生了显著的活性增强。由于TiO₂在许多基于能源的应用中具有巨大潜力，我们的拓扑化学方法为生产具有良好控制和高反应活性暴露晶面的高结晶度锐钛矿TiO₂提供了一种低成本、绿色且可大规模扩展的途径。
