1. 1.Please describe two template-based fabrication strategies for highly ordered nanostructures! 2.How can core-shell nanostructures be synthesized? 3.Which advantages provide highly ordered nanostructures and for which application are they beneficial? 4.What are the allotropes (dt. Strukturformen) of carbon? Please describe their structures. 5.What are zigzag and armchair carbon nanotubes? How to define them? 6.Why are carbon nanotubes and graphene can be used as functional materials for high-sensitivity sensors? 7. How do you compare the synthesis of carbon nanotubes and graphene in terms of similarity and differences?

2. 1. Please describe two template-based fabrication strategies for highly ordered nanostructures! Features: - Highly ordered pored - High surface area - Nanosized pores, controllable - Adjustable thickness

5. 2. How can core-shell nanostructures be synthesized? Example 1

6. 2. How can core-shell nanostructures be synthesized? Example 2 Example 3

7. Features and requirements: - nanostructure is necessary, e.g. AAO templates - composition of two materials - different functions of these materials, e.g. absorption & conductivity - often combination of diffenernt fabrication methodes, e.g. electrodeposition and ALD Core/Shell structures

8. 3. Which advantages provide highly ordered nanostructures and for which application are they beneficial? Advantages: - Improving light absorption efficiency - Decoupling of the directions of light absorption and charge-carrier collection - Providing large contact area between (photo)electrodes and electrolyte - Enhancing the overall charge transfer kinetics - Large surface area for electrochemical reactions - Full utilization of active materials and a short ion diffusion pathway - Conductive core to provide fast electron transport (core/shell structure) - Void spaces for restraining structural deviation of the single unit during charge-discharge process

9. 3. Which advantages provide highly ordered nanostructures and for which application are they beneficial? Applications: - Supercapacitors - Batteries - Solar water splitting - Gassensors - Biological experiments - …

10. 4. What are the allotropes (dt. Strukturformen) of carbon? Please describe their structures. Allotrophes: a) diamond b) graphite c) lonsdaleite (hexagonaler Diamant) d–f) fullerenes (C60, C540, C70) g) amorphous carbon h) carbon nanotube

11. 5. What are zigzag and armchair carbon nanotubes? How to define them? Lattice vector: a 1, a 2 roll-up vector: C h =n*a 1 +ma 2 zigzag: m=0  =0° armchair: m=n  =30°

12. 6. Why are carbon nanotubes and graphene can be used as functional materials for high-sensitivity sensors? Sensors: - certain stimulus  certain output - selectivity - efficiency - properties can be enhanced by tuning size, structure and shape of (nano)material CNT: - electronic properties largely affected by exposure of gases - response was linear with the concentration in the range from sub-ppm to hundreds of ppm (NO 2 )  O 2 : extremely sensitive, due to charge transfer complex C and O  NO 2 : electrons are withdrawn in CNT-based FET  NH 3 : electrons are donated

13. 7. How do you compare the synthesis of carbon nanotubes and graphene in terms of similarity and differences? Synthesis: CNT: - arc-discharge in vacuum or in solution (ADS) - laser ablation - Plasma-Enhanced or Thermal Chemical Vapor Deposition Graphene: - pull graphene sheets with adhesive tape from graphite - Chemical exfoliation - Total organic synthesis - Epitaxial growth and chemical vapor deposition Parameters: Differences: - high or low temperature - high or low pressure - gas or solution phase Similarities: -top-down (starting from graphite) - bottom-up (CVD growth)