Redox-Active Mixed-Linker Metal-Organic Frameworks with Switchable Semiconductive Characteristics for Tailorable Chemiresistive Sensing

Metal-organic frameworks (MOFs), with diverse metal nodes and designable organic linkers, offer unique opportunities for the rational engineering of semiconducting properties. In this work, we report a mixed-linker conductive MOF system with both tetrathiafulvalene and Ni-bis(dithiolene) moieties, which allows the fine-tuning of electronic structures and semiconductive characteristics. By continuously increasing the molar ratio between tetrathiafulvalene and Ni-bis(dithiolene), the switching of the semiconducting behaviors from n-type to p-type was observed along with an increase in electrical conductivity by 3 orders of magnitude (from 2.88x10(-7) S m(-1) to 9.26x10(-5) S m(-1)). Furthermore, mixed-linker MOFs were applied for the chemiresistive detection of volatile organic compounds (VOCs), where the sensing performance was modulated by the corresponding linker ratios, showing synergistic and nonlinear modulation effects.

Automated summary

In this study, a mixed-linker conductive MOF system was developed by incorporating tetrathiafulvalene and Ni-bis(dithiolene) moieties, allowing precise control over electronic structures and semiconductor characteristics by adjusting their molar ratio. The semiconducting behavior of the MOF system can be switched from n-type to p-type by increasing the ratio of tetrathiafulvalene to Ni-bis(dithiolene), resulting in a three orders of magnitude increase in electrical conductivity. Additionally, the mixed-linker MOFs showed synergistic and nonlinear modulation effects on the chemiresistive detection of VOCs, with sensing performance modulated by the linker ratios.