Ilhan Cansu, Caffrey Eoin, Liu Shixin, Munuera Jose, Sofer Zdeněk, Plutnarová Iva, Morris Michael A, Coleman Jonathan N, Carey Tian
School of Chemistry, CRANN & AMBER Research Centres, Trinity College Dublin, Dublin 2, Ireland.
School of Physics, CRANN & AMBER Research Centres, Trinity College Dublin, Dublin 2, Ireland.
Nanoscale. 2025 Jul 22. doi: 10.1039/d5nr01217a.
We undertake electrochemical exfoliation of a 2D semiconductor platinum diselenide, PtSe and investigate the piezoresistance response of a solution-processed network. Due to the large PtSe aspect ratios, exceeding 300, we achieve conformal flake-to-flake junctions and good inter-flake electrical coupling. Our measured piezoresistive gauge factor is negative (-5.45), consistent with the intrinsic negative gauge factor of PtSe. This negative network gauge factor implies that strain is transferred from the substrate to the nanosheets. However, detailed modelling shows that the strain transferred to the nanosheets is much smaller than the applied strain, showing that conformal junctions do not necessarily lead to good mechanical coupling between nanosheets. Our model implies that this gauge factor is consistent with a strain transfer efficiency of 8.5%. Our strain sensor also demonstrated a cyclic response for over 1000 cycles, enabling the sensor to be used in future flexible optoelectronics applications.
我们对二维半导体二硒化铂（PtSe₂）进行了电化学剥离，并研究了溶液处理网络的压阻响应。由于PtSe₂的长宽比很大，超过300，我们实现了薄片间的共形结和良好的片间电耦合。我们测得的压阻应变片系数为负（-5.45），这与PtSe₂固有的负应变片系数一致。这种负网络应变片系数意味着应变从基底转移到了纳米片上。然而，详细的建模表明，转移到纳米片上的应变远小于施加的应变，这表明共形结不一定会导致纳米片之间良好的机械耦合。我们的模型表明，该应变片系数与8.5%的应变转移效率一致。我们的应变传感器还展示了超过1000次循环的循环响应，使该传感器能够用于未来的柔性光电子应用。
