Alpha Ni (oh) < Sub > 2 < / Sub > And Alpha Ni (oh) < Sub > 2 < / Sub > / Rgo Composite Material Synthesis And No < Sub > X < / Sub > Gas Sensitive Sex Research

In this paper, the α-Ni（OH）₂nanocrystalline with3D hierarchical structure andα-Ni（OH）₂/rGO nanocomposites was prepared through simple reflux methods.By adding of SDBS, the α-Ni（OH）₂with hierarchical pores and interlayer anions,water molecules was synthetized. Especially, the sensing mechanism of α-Ni（OH）₂with3D hierarchical structure was discussed in two aspects:1) relation between hier-archical pores and diffusion, adsorption/desorption of NO_x gas on surface ofα-Ni（OH）₂nanocrystalline;2) effect of chemical composition of layered double hy-droxides like （LDHs-like） structure on the ability of proton transportation between ad-jacent NiOH layers and between overlapped ultrafine nanocrystals. The results demon-strate that abundant mesoporous（3.9nm,34nm） and unique chemical composition([Ni（OH）_0.90]（OCN）_0.10（CO₃）_0.47（SO₄）_0.02（NO₃）_0.01（H₂O）_0.41) enhance the gas-sensingproperties and service lifetime effectively to NO_x.The morphology-controllable α-Ni（OH）₂/rGO nanocomposites was synthesizedwithout using any surfactant. Researching about the growing process of α-Ni（OH）₂TNs on rGO indicate that the effective combination between α-Ni（OH）₂and rGO sup-press α-Ni（OH）₂from growing up and aggregating, on the other hand, GO was peeledinto thinner rGO sheets by intercalating of Ni²⁺. Gas sensing results show that,α-Ni（OH）₂/rGO nanocomposite has better sensitivity and faster response than theα-Ni（OH）₂with3D hierarchical structure. The problem of slow response speed anddifficult to recovery of GO sensor is solved.In summary, higher sensitivity, fast-response, good repeatability and longer ser-vice life enable the α-Ni（OH）₂nanocrystalline with3D hierarchical structure andα-Ni（OH）₂TNs/rGO nanocomposite as a promising material in gas sensing field.