[10a-B12-1~12] 12.3 Functional Materials and Novel Devices

9:45 AM - 10:00 AM JST(12:45 AM - 1:00 AM UTC)Presentation by Applicant for JSAP Young Scientists Presentation Award

[10a-B12-4] Negative Photoconductivity of Potassium Poly(heptazine imide)

〇Kota Nakamura¹, Ibuki Oku¹, Kaname Kanai¹ (1.Tokyo Univ. of Sci.)

Keywords:

Organic semiconductor,Negative photoconductivity,Poly(heptazine imide)

Negative photoconductivity (NPC) is a phenomenon in which the electrical conductivity of a material decreases upon light irradiation. In this study, we focused on potassium poly(heptazine imide) (K-PHI), a carbon nitride polymer that exhibits NPC. It has been reported that ionic conduction dominates in the low-voltage region, whereas carrier conduction becomes dominant at higher applied voltages. By comparing the photoresponse in different voltage regions, we investigated the origin of NPC in K-PHI. As a result, NPC was observed only in the voltage region where carrier conduction occurs and was absent in the ionic-conduction-dominated region. These findings indicate that carrier conduction plays a crucial role in the emergence of NPC and suggest the involvement of carrier trapping in the underlying mechanism.