Charge-density-wave at elevated temperatures in 1T-TaS2 ink-printed devices

We present results from low-frequency noise and current–voltage measurements on an ink-printed 1T-TaS2 layer on a ceramic substrate, situated between interdigitated platinum electrodes. The measurements were conducted at elevated temperatures and under UV exposure. A charge-density-wave (CDW) phase transition was detected by analyzing the temperature dependence of the sample resistance and low-frequency noise by identifying Lorentzian-type noise spectra close to the phase transition temperature. The low-frequency noise data allowed us to determine the activation energy, Ea ≅ 4 eV. The samples consisted of 1T-TaS2 flakes held together solely by van der Waals forces between the platinum electrodes. This structure is more susceptible to mechanical tension caused by temperature changes but offers improved sensing capabilities compared to structures that combine 1T-TaS2 flakes with stabilizing polymers or glycols. We conclude that the Lorentzian-type noise spectra observed in the investigated 1T-TaS2 layer are linked to CDW phenomena at temperatures near 350 K.