**Defect Engineered 2D Materials for Energy Applications**

Sai Sunil Kumar Mallineni, Sriparna Bhattacharya, Fengjiao Liu, Pooja Puneet, Apparao Rao, Anurag Srivastava and Ramakrishna Podila

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/64605

#### **Abstract**

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82 Two-dimensional Materials - Synthesis, Characterization and Potential Applications

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2014;5:4470.

223.

Two-dimensional (2D) materials display unique properties that could be useful for many applications ranging from electronics and optoelectronics to catalysis and energy storage. Entropically necessary defects are inevitably present in 2D materials in the form of vacancies and grain boundaries. Additional defects, such as dopants, may be intentionally introduced to tune the electronic structure of 2D materials. While defects are often perceived as performance limiters, the presence of defects and dopants in 2D materials results in new electronic states to endow unique functionalities that are otherwise not possible in the bulk. In this chapter, we review defect-induced phenom‐ ena in 2D materials with some examples demonstrating the relevance of defects in electronic and energy applications. In particular, we present how the (i) N-dopant configuration in graphene changes the electron-phonon interactions, (ii) zigzag defects and edges in graphene increase the quantum capacitance to improve energy density of graphene-based supercapacitors, and (iii) charged grain boundaries in exfoliated Bi2Te3 preferentially scatter low-energy electrons and holes to enhance the thermoelectric performance.

**Keywords:** Engineering defects, 2D materials, Quantum capacitance, Energy storage
