| Novel applications of nanostructures in catalysis, electronics, photonics, andbionanotechnology are driving the exploration of synthetic approaches to control andmanipulate their chemical composition, structure, and morphology. As well as thedesign of synthetic strategies to produce a new class of nanoscale materials, recentdevelopments have enabled the chemical transformation of one crystalline materialinto another desired target material. Three of the most important methods for chemicaltransformation are the ion-exchange reaction, the Kirkendall effect, andstabilizer-depleted binary semiconductor nanocrystals. The first two methods havebeen shown to produce nanomaterials with a diverse structure and a controlledcomposition, but are not suitable to transform binary materials into unarysemiconductors. Interestingly, the third method has been successfully adopted byKotov and Tang et al. to convert CdE （E=Se, Te） into unary E solid nanowires andangled Te nanocrystals, but is still not suitable to produce porous materials. Amongthe various materials, porous nanostructures have received increasing attention owingto their improved chemical and physical performance over solid materials, as well astheir intriguing applications in a variety of fields. In comparison with theirpolycrystalline counterparts, single-crystal-like materials have been found to reducethe number of defects, and have enhanced electron-transfer and catalytic properties.However, the development of a facile technique to transform binary materials intothree-dimensional （3D） porous unary semiconductors, especially withsingle-crystallike structures, remains a great challenge.Here we have developed a facile approach to transform the as-prepared Sb2Te3nanoplates into3D porous single-crystal-like network-structured Te nanoplates. Andwe also have explored and proposed the reaction mechanism of chemicaltransformation. The as-prepared Sb2Te3nanoplates were transformed into3D poroussingle-crystal-like network-structured Te nanoplates through the dissolution of Sb3+ions, the oxidation of Te2-ions to Te0, and a subsequent Ostwald ripening processinduced by oxygen and tartaric acid （TA）. We have demonstrated that this method canbe adopted to convert Sb2Te3nanoplates into porous heterogeneous In/Te networks through the reduction of InCl3during the chemical transformation of Sb2Te3.Furthermore, the as-prepared porous Te plates can be used as the template for thehighly efficient synthesis of3D porous network-structured noble-metal nanoplateswith promising applications. We have used porous network-structured Te nanoplatesas templates to prepare high-quality porous nanothread-based noble-metal Pt, Aunanoplates and porous nanotube-based Pd plates. Thus, the as-prepared porousnetwork-structured Te plate could possibly be used as a general template to produceporous nanotube-based （or solid-nanothread-based） plates of metal tellurides withpotential applications in electronics. The chemical composition, structure, andmorphology of products as well as the chemical transformation mechanism werecharacterized and analyzed by SEM, EDX, XRD, TEM, SAED, HRTEM, EELS andICP. |
