Observation of Ultrahigh Photoconductivity in DNA‐MoS2 Nano‐Biocomposite

Abstract A nano‐biocomposite film with ultrahigh photoconductivity remains elusive and critical for bio‐optoelectronic applications. A uniform, well‐connected, high‐concentration nanomaterial network in the biological matrix remains challenging to achieve high photoconductivity. Wafer‐scale continuous nano‐biocomposite film without surface deformations and cracks play another major obstacle. Here we observed ultrahigh photoconductivity in DNA‐MoS2 nano‐biocomposite film by incorporating a high‐concentration, well‐percolated, and uniform MoS2 network in the ss‐DNA matrix. This was achieved by utilizing DNA‐MoS2 hydrogel formation, which resulted in crack‐free, wafer‐scale DNA‐MoS2 nano‐biocomposite films. Ultra‐high photocurrent (5.5 mA at 1 V) with a record‐high on/off ratio (1.3×106) was observed, five orders of magnitude higher than conventional biomaterials (∼101) reported so far. The incorporation of the Wely semimetal (Bismuth) as an electrical contact exhibited ultrahigh photoresponsivity (2.6×105 A/W). Such high photoconductivity in DNA‐MoS2 nano‐biocomposite could bridge the gap between biology, electronics, and optics for innovative biomedicine, bioengineering, and neuroscience applications. This article is protected by copyright. All rights reserved