选择Keggin型12-磷钨酸(TPA)及其钠盐(NaTP)水溶液为亚相,用四(4-N,N-二乙胺基苯基)卟啉化合物(H2TNPP)自组装膜为功能模板,采用低成本的QLS法成功制备了2种新型有机/无机复合材料:H2TNPP/TPA,H2TNPP/NaTP QLS薄膜.薄膜结构、形貌及半导体性质测试发现:H2TNPP分子在H2TNPP/TPA,H2TNPP/NaTP复合膜中均采取H-聚集模式,TPA亚相上H-聚集程度更大.而在纯H2TNPP膜中其为J-聚集模式.3种薄膜表面均为纳米颗粒形貌,以H2TNPP/NaTP膜表面颗粒均一,颗粒尺寸最小(～60 nm),H2TNPP/TPA膜表面缺陷较多,颗粒尺寸最大(～150 nm).薄膜导电性依次为H2TNPP/NaTP (3.00×10-5 S·cm-1)＞H2TNPP/TPA(2.49×10-5 S·cm-1)＞H2TNPP膜(1.53×10-5 S·cm-1).常温气敏测试发现:3种薄膜在30 s内对浓度小于1.88 mg·m-3的NO2气体都有响应,灵敏度依次为H2TNPP/NaTP(43％)＞H2TNPP膜(16％)＞H2TNPP/TPA(4.5％).具有最小颗粒尺寸和最高导电性的H2TNPP/NaTP复合薄膜具有最高的灵敏度,并且对NO2检测限低至0.094 mg· m-3.显示出了非常高的实际应用价值.本研究为制备低成本、高灵敏度、环境友好的快速室温NO2气敏器件提供了一种新的策略.%The novel H2TNPP/TPA and H2TNPP/NaTP organic-inorganic hybrid nanocomposites [H2TNPP =tetrakis(4-N,N-diethylaminophenyl)porphyrin,TPA=the phosphotungstic acid and NaTP=sodium phosphotungstate] are fabricated by a simple QLS method.H-type molecular stacking mode with a tilted edge-on orientation of the H2TNPP has been formed in the hybrid films.The intermolecular face-to-face π-π interaction and film microstructures are effectively improved by introducing inorganic TPA and NaTP within the organic H2TNPP films,compared with the pure H2TNPP film.In particular,good film-conductivity,smaller grain size and large specific surface area of H2TNPP/NaTP hybrid film render it excellent sensing property for NO2 gas with the lowest detection limit of 0.094 mg· m-3 and highest sensitivity (43％) among the three kinds of films in room temperature,suggesting the great potential of semiconducting H2TNPP/NaTP organic-inorganic hybrid nanocomposites in the field of chemical sensors.The present result provides a new strategy to obtain high performance room-temperature gas sensors by the construction of organic/inorganic hybrid structure combined with a low-cost solution-based method.
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