Thermoelectric properties of the hexagonal- and square-shaped monolayers of ZnO Bakhtiar Ul Haq, S. AlFaify and R. Ahmed Eur. Phys. J. Plus, 136 7 (2021) 794 Published online: 31 July 2021 DOI: 10.1140/epjp/s13360-021-01777-2