NixCu3−x(HHTP)2 decorated poly-pyrrole porous nanocomposites for highly selective and stable hydrogen sulfide sensing at room temperature

Hydrogen sulfide (H 2 S) sensing with high selectivity and stability is required for environmental monitoring at room temperature , however, needs further exploring. Here, Ni x Cu 3−x (HHTP) 2 decorated over poly-pyrrole nanocomposites {Ni x Cu 3−x (HHTP) 2 /PPy NCPs, HHTP = 2,3,6,7,10,11-hexahydroxytriphenylene} have been developed for highly selective and stable H 2 S sensing at room temperature (∼ 25 ⁰C), which have been synthesized by firstly oxidating polymerizing poly-pyrrole nanoparticles and subsequently decorating with Ni x Cu 3−x (HHTP) 2 metal-organic frameworks (MOFs) via a hydrothermal process. Typically, the Ni x Cu 3−x (HHTP) 2 /PPy NCPs are observed with spiny surface and are characterized with amorphous crystallization. Beneficially, the Ni x Cu 3−x (HHTP) 2 /PPy NCPs show excellent selectivity to H 2 S even in the presence of other interfering gases and display a 70 days-long stability that maintains 77.3% response at room temperature (∼ 25 ⁰C). Further, the sensor prototypes enable to detect H 2 S as low as 500 ppb and show stability against humidity, respectively. Theoretically, such excellent H 2 S sensing performance might be attributed to the charge transfer between H 2 S molecules and utilized copper, fast charge transports via forming bimetallic MOFs and the counteraction of PPy NPs to interfering gas. Practically, a H 2 S sensing device built with the Ni x Cu 3−x (HHTP) 2 /PPy prototype has been integrated to detect H 2 S with excellent sensing response.