Noble metal nanoparticles functionalized conductive Co3(hexaiminotriphenylene)2 chemiresistor for hydrogen sulfide detection at Room-Temperature.

• Conductive Co 3 (HITP) 2 nanomaterial was synthesized and used for H 2 S detection at room temperature for the first time. • Conductive Co 3 (HITP) 2 nanomaterial showed high response and good selectivity toward H 2 S at room temperature under various humidity. • Optimum Pd, Au and Pt NPs modification could significantly enhance the sensing properties of Co 3 (HITP) 2. • The catalytic effect of Pd, Au and Pt NPs on conductive Co 3 (HITP) 2 for H 2 S sensing was also discussed. Metal-organic frameworks (MOFs) applied in chemiresistors is principally limited by their poor conductivity and low catalytic activity. Herein, we report an intrinsically conductive two-dimensional (2D) MOF Co 3 (hexaiminotriphenylene) 2 [Co 3 (HITP) 2 ], for hydrogen sulfide (H 2 S) sensing at room temperature (RT). The proposed conductive Co 3 (HITP) 2 sensor exhibits high sensitivity and good selectivity toward H 2 S under various relative humidity (RH) at RT. Meanwhile, different amounts of catalytic Pd nanoparticles (NPs) are embedded in conductive Co 3 (HITP) 2 for further improving the gas sensing performances. The sensing results confirm that the 2 mol% Pd functionalized Co 3 (HITP) 2 gas sensor presents the best sensing properties to H 2 S under different humidity at RT. We extended the catalytic metal NPs to Au and Pt, and Au or Pt loading conductive Co 3 (HITP) 2 sensors also show remarkably enhanced H 2 S sensing performance including high response and low limit of detection (LOD). While, the pristine and noble metal NPs functionalized Co 3 (HITP) 2 gas sensors are affected by humid atmosphere due to water vapor adsorption on Co 3 (HITP) 2. Finally, the catalytic effect of noble metal NPs on conductive Co 3 (HITP) 2 for H 2 S sensing is also discussed. The obtained results provide a key insight into the high-performance conductive Co 3 (HITP) 2 based gas sensors work at RT for H 2 S detection. [ABSTRACT FROM AUTHOR]