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报道了锶掺杂二硫化钼(Sr-MoS2)改变(101)面间距,增强了压电近红外NH3BH3释放氢气.X射线衍射(XRD)显示,锶原子掺杂使得MoS2晶体中(002)晶面的面间距从6.71?压缩到6.43?,但其衍射峰显著增强,表明锶掺杂促进了(002)晶面的晶化.与此同时,锶掺杂使得(101)晶面的面间距从2.66?增加到2.70?,显示锶垂直于(101)晶面生长,这是因为锶的原子半径2.15?大于钼的原子半径2.01?.透射电子显微镜(TEM)观测到规整的(002)晶面,其面间距6.43? 与XRD衍射角计算值一致,显示锶掺杂进入了MoS2晶格中.X射线光电子能谱(XPS)证实锶存在于MoS2中.紫外-可见-近红外(UV-Vis-NIR)漫反射光谱显示Sr-MoS2带隙为0.84 eV,而纯MoS2带隙为0.94 eV,这种带隙的降低有利于吸收近红外光.在最佳条件下,Sr-MoS2压电近红外光催化0.05 mol·L-1 NH3BH3水溶液,在12 h氢气产率是1.22 mmol·(g·h)-1,而纯MoS2的氢气产率只有0.35 mmol·(g·h)-1.由于压电效应是结构的不对称所致,因此,锶掺杂导致MoS2(101)面间距增加,从而导致压电效应的增加,最终导致产氢率的提高.“,”Piezo-electric effect is ascribed to the asymmetry of structure forced by mechanics. The paper reports the effi-cient release of hydrogen from ammonia borane containing 19.6 wt％ of hydrogen mass based on the piezoelectric photo-catalysis of strontium-doped MoS2(Sr-MoS2) due to the widened d-spacing of plane (101) as the catalyst under near-in-frared irradiation. XRD patterns display that the doping of strontium atoms shortened the d-spacing of the (002) planes from 6.71 ? to 6.43 ?,but facilitated the crystallization of the (002) planes. It also shows that the strontium atoms in MoS2 grew and were perpendicular to the (101) planes during doping and widened the d-spacing of the (101) planes from 2.66 ? to 2.70 ? because the atom radius of strontium (2.15 ?) is larger than that of molybdenum (2.01 ?). The more regularly arranged (002) planes were observed,and the d-spacing of 6.43 ? was in agreement with the value calcu-lated by XRD angle,which confirms the existence of strontium in MoS2 lattices. UV-Vis-NIR diffuse reflectance spectra indicated that the band gap of Sr-MoS2 is 0.84 eV,whereas the one of the as-synthesized MoS2 is 0.94 eV. Under optimal conditions,the hydrogen yield based on Sr-MoS2 catalyst from aqueous NH3BH3 solution was 1.22 mmol·(g·h)-1,whereas that of pristine MoS2 was only 0.35 mmol·(g·h)-1 under ultrasonic and 850 nm near-infrared irradiation at 12 h. The boosted yield of hydrogen was assigned to the enhanced piezoelectric effect due to the doping of strontium in MoS 2 result-ing in the widened d-spacing of plane (101),because the piezo-current of Sr-MoS2 was much larger than that of pristine MoS2.