Flexible Thermoelectric ZnO–Organic Superlattices on Cotton Textile Substrates by ALD/MLD

The thermoelectric properties of both pristine ZnO and ZnO–organic superlattice thin films deposited on a cotton textile are investigated. The thin films are fabricated by atomic layer deposition/molecular layer deposition, using hydroquinone as the organic precursor for the superlattices. The resulting thin‐film coatings are crystalline, in particular when deposited on a textile substrate with a thin predeposited Al₂O₃ seed layer. The thermoelectric properties of the ZnO and ZnO–organic superlattice coatings are comparable to those for thin films deposited on conventional inorganic substrates; Al doping can be employed to further improve the thermoelectric properties. The ZnO–organic superlattice thin films moreover show enhanced resistance to mechanical strain. Due to the higher flexibility and lower thermal conductivity in comparison to pristine ZnO thin films, the ZnO–organic superlattice thin films are a possible material platform for flexible thermoelectrics that can be integrated in textiles and applied in wearable electronics.