biostudies-literatureZhang XNational Natural Science Foundation of ChinaNatural Science Foundation of Heilongjiang Province8768-8777https://www.ebi.ac.uk/biostudies/studies/S-EPMC9062008biostudies-literatureUnknown9(16)To develop an ultra-sensitive and selective NO x gas sensor with an ultra-low detection limit, expanded graphite/NiAl layered double hydroxide (EG/NA) nanowires were synthesized by using hydrothermal method with EG as a template and adjusting the amount of urea in the reaction. X-ray diffraction and transmission electron microscopy showed EG/NA3 nanowires with a diameter of 5-10 nm and a length greater than 100 nm uniformly dispersed on the expanded graphite nanosheet (>8 layers). The synergy between NiAl layered double hydroxide (NiAl-LDH) and expanded graphite (EG) improved the gas sensing properties of the composites. As expected, gas sensing tests showed that EG/NA composites have superior performance over pristine NiAl-LDH. In particular, the EG/NA3 nanowire material exhibited an ultra-high response (R a/R g = 17.65) with ultra-fast response time (about 2 s) to 100 ppm NO x , an ultra-low detection limit (10 ppb) and good selectivity at room temperature (RT, 24 ± 2 °C), which could meet a variety of application needs. Furthermore, the enhancement of the sensing response was attributed to the nanowire structure formed by NiAl-LDH in the EG interlayer and the conductive nanonetwork of interwoven nanowires.RSC advancesExpanded graphite/NiAl layered double hydroxide nanowires for ultra-sensitive, ultra-low detection limits and selective NO x gas detection at room temperature.PMC9062008216701074721671060D2015003Liu ZZhang XWang DIkram MXue JLi LShi KTeng LfalseExpanded graphite/NiAl layered double hydroxide nanowires for ultra-sensitive, ultra-low detection limits and selective NO x gas detection at room temperature.To develop an ultra-sensitive and selective NO x gas sensor with an ultra-low detection limit, expanded graphite/NiAl layered double hydroxide (EG/NA) nanowires were synthesized by using hydrothermal method with EG as a template and adjusting the amount of urea in the reaction. X-ray diffraction and transmission electron microscopy showed EG/NA3 nanowires with a diameter of 5-10 nm and a length greater than 100 nm uniformly dispersed on the expanded graphite nanosheet (>8 layers). The synergy between NiAl layered double hydroxide (NiAl-LDH) and expanded graphite (EG) improved the gas sensing properties of the composites. As expected, gas sensing tests showed that EG/NA composites have superior performance over pristine NiAl-LDH. In particular, the EG/NA3 nanowire material exhibited an ultra-high response (R a/R g = 17.65) with ultra-fast response time (about 2 s) to 100 ppm NO x , an ultra-low detection limit (10 ppb) and good selectivity at room temperature (RT, 24 ± 2 °C), which could meet a variety of application needs. Furthermore, the enhancement of the sensing response was attributed to the nanowire structure formed by NiAl-LDH in the EG interlayer and the conductive nanonetwork of interwoven nanowires.2019-01-01T00:00:00Z2019 Mar2025-04-19T13:17:58.854Z2025-04-19T13:17:58.854ZS-EPMC90620083551768310.1039/c9ra00526a