一种基于化学拓扑变换合成多孔二维过渡金属氧化物纳米片的通用策略

A universal strategy for the synthesis of porous twodimensional transition metal oxide nanosheets based on chemical topology transformation

二维(2D)过渡金属氧化物(TMO)由于其丰富的活性位点,快速的离子传输速率和较短的载流子迁移距离引起了广泛关注.但是,当前的合成策略通常局限于本质分层的化合物或基于牺牲模板的方法.本文中,我们报道了一种通过相应过渡金属硒化物的化学拓扑转移制备超薄二维多孔TMO纳米片的通用策略.值得注意的是,所制备的2D TMO纳米片不仅可以完美地继承过渡金属硒化物的2D拓扑结构,而且由于晶格生长中的应力释放产生了大量的孔洞结构.此外,我们基于原位氧化相应的超薄WSe_(2),Mo Se_(2)和Co_(0.85)Se纳米片,成功制备了多孔超薄WO_(3),MoO_(3)和Co_(3)O_(4)纳米片.所制备的多孔二维WO_(3)纳米片出色的气敏性能和光探测性能进一步表明了该制备策略具有广阔的应用前景.

Two-dimensional(2D)transition metal oxides(TMOs)have attracted much attention for various applications,owing to the abundance of active sites,rapid ion transmission speed,and short carrier migration distance.However,the current preparation strategies are usually limited to producing intrinsically layered compounds or sacrificing template.Here,we report a universal strategy for preparing ultrathin porous 2D TMO nanosheets by chemical topological transformation of the corresponding transition metal selenides.We observed that the as-prepared 2D TMO nanosheets not only perfectly inherit the transition metal selenides’2D topological structure,but also possess numerous pore structures formed as a way to release the structural stress associated with lattice growth.As a proof of concept,ultrathin porous WO_(3),Mo O_(3),and Co_(3)O_(4) nanosheets were successfully prepared based on the in-situ oxidation of the corresponding ultrathin WSe_(2),MoSe_(2),and Co_(0.85)Se,respectively.The outstanding sensing properties and photodetector performance displayed by the as-prepared porous 2D WO_(3) nanosheets further indicate the promising prospects of topology transformation for the preparation of porous 2D TMO nanosheets.