& Materials Science | Hot Paper| Recycling Nanowire Templates for Multiplex Templating Synthesis: A Green and Sustainable Strategy Jin-Long Wang, [a] Jian-Wei Liu, [a] Bing-Zhang Lu, [a] Yi-Ruo Lu, [a] Jin Ge, [a] Zhen-Yu Wu, [a] Zhi- Hua Wang, [a] Muhammad Nadeem Arshad, [c] and Shu-Hong Yu* [a, b] Abstract: Template-directed synthesis of nanostructures has been emerging as one of the most important synthet- ic methodologies. A pristine nanotemplate is usually chemically transformed into other compounds and sacri- ficed after templating or only acts as an inert physical template to support the new components. If a nanotem- plate is costly or toxic as waste, to recycle such a nanotem- plate becomes highly desirable. Recently, ultrathin telluri- um nanowires (TeNWs) have been demonstrated as versa- tile chemical or physical templates for the synthesis of a di- verse family of uniform 1D nanostructures. However, ultra- thin TeNWs as template are usually costly and are discarded as toxic waste in ionic species after chemical re- actions or erosion. To solve the above problem, we con- ceptually demonstrate that such a nanotemplate can be economically recycled from waste solutions and repeated- ly used as template. One dimensional (1D) nanostructures with fascinating proper- ties derived from unique geometric characteristics have been widely studied in electronic, optoelectronic, sensors, and elec- tromechanical fields. [1] Various strategies, including both physi- cal and chemical methods, have been developed to fabricate uniform 1D nanomaterials. [2] Template-directed synthesis, among the various methods, has been one of the most straightforward routes to 1D nanostructure because of its simple, high-throughput procedure and variability in control- ling structure and chemical composition of the products. [3] The templates are always used only one time and wasted after the reactions. [2, 3a,b] From economical and environmental view- points, it is highly important to develop a green process for templating synthesis, especially for large-scale templating syn- thesis for future industrialized production. However, to date, little attention has been paid to the recycling and reproducing of such sacrificial but valuable templates after the chemical re- action. Ultrathin tellurium nanowires (Te NWs) with high aspect ratios have been widely studied [4] and have great potential for fabrication of nanodevices. [5] As a versatile and reactive tem- plate, Te NWs can be used as either a chemical transforming template or a physical template to synthesize a family of tellu- rium-based nanostructures and other 1D nanostructures. [6] For example, a series of metal telluride nanowires (MxTe, M = Ag, Pb, Cd, Bi, Zn, Cu, etc.) and noble metal nanowires such as Pt, Pd, AuPtPd nanowires can be easily synthesized by using Te NWs as the chemical transforming template. [7] In addition, Te NWs can be used as a physical template to fabricate carbon nanofibers (CNFs) with various functionalities. [3a, 8] These metal telluride nanowires and CNFs have widespread applications in diverse fields. However, tellurium nanowire precursor is gener- ally wasted after the templating synthesis, which commonly exists in a form of tellurite in solution. [7f,9] To date, how to deal with the byproducts of the templating reactions especially for the sacrificial template reactions has been largely ignored. Generally, the most effective way to deal with the byproducts of chemical reactions is to recycle them back to useful prod- ucts. Herein, we report a new concept on recycling ultrathin tellu- rium nanowire templates that can be repeatedly used as tem- plate to synthesize other 1D nanostructures, such as CNFs, Pt/ Pd@CNFs, Pt nanotubes/nanoparticles composites (NTs@NPs) and Pd NWs. After template synthesis, high-quality Te NWs can be reproduced from the collected solution by adjusting the re- action conditions such as pH and the concentration of the so- lution. The recycle efficiency is more than 80 % relative to the pristine Te NWs used as template to synthesize Pd NWs, CNFs, 65% for Pt NTs@NPs and more than 70 % for Pt@CNFs, Pd@CNFs systems in the first recycling process. We anticipate this template recycle strategy will largely decrease the cost of the products derived from tellurium and at the same time avoid contamination of the environment. The recycling proce- dure for the pristine Te NWs used as template for synthesis of various 1D functional nanomaterials is illustrated in Figure 1 and the typical reactions can be formulated as follows: [a] J.-L. Wang, + Dr. J.-W. Liu, + B.-Z. Lu, Y.-R. Lu, J. Ge, Z.-Y. Wu, Z.-H. Wang, Prof. Dr. S.-H. Yu Division of Nanomaterials and Chemistry Hefei National Laboratory for Physical Sciences at Microscale Collaborative Innovation Center of Suzhou Nano Science and Technology Department of Chemistry, University of Science and Technology of China Hefei, Anhui 230026 (P.R. China) E-mail : shyu@ustc.edu.cn [b] Prof. Dr. S.-H. Yu Institute of Solid State Physics, Hefei Institutes of Physical Science Chinese Academy of Sciences, Hefei 230031 (China) [c] Dr. M. N. Arshad Center of Excellence for Advanced Materials Research Chemistry Department, Faculty of Science King Abdulaziz University, Jeddah 21589 (Saudi Arabia) [ + ] These authors contributed equally to this work. Supporting information for this article is available on the WWW under http ://dx.doi.org/10.1002/chem.201406022. Chem. Eur. J. 2015, 21,1–6  2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim 1 && These are not the final page numbers! ÞÞ Communication DOI: 10.1002/chem.201406022