《厦门大学学报（自然科学版）》

利用宽带和频光谱(BB-SFG)对Cu和Au表面的吡咯烷二硫代甲酸铵(APDTC)自组装膜进行研究.结果发现在Cu表面APDTC的SFG共振谱峰为叠加在基底宽带非共振谱峰上的正峰,其与Cu基底的相对相位约为0; 而在Au表面,共振谱峰为负峰,相对相位约为π.烷基十八硫醇自组装膜的SFG中也观察到相似的线型变化.X射线衍射(XRD)谱分析表明Cu表面有氧化峰,而Au表面没有,这是由于Cu在自组装过程中发生了自发氧化.因此,Cu表面的SFG信号来自于氧化物,而Au表面的信号来自于金属本身,两者绝对相位的不同造成其表面分子与基底相对相位的差异,使APDTC分子SFG共振谱峰分别表现为正峰和负峰.

Self-assembled monolayers(SAMs)on metal surface are of great significance to study the interaction between molecules and interfacial materials.In this study,the spectral lineshape of ammonium pyrrolidine dithiocarbamate(APDTC)SAMs on Au and Cu surfaces was studied with broadband sum frequency generation spectroscopy(BB-SFG).The results showed that the resonant SFG bands on Cu surface were represented as peaks superimposed on the broad non-resonant substrate SFG band,and the relative phase between the resonant and non-resonant was about zero.While on Au surface,the resonant bands were represented as dips,and the relative phase was about π.Similar spectral lineshapes were observed in the BB-SFG spectra of 1-octadecanethiol SAMs.XRD patterns showed that oxidation had occurred on the Cu surface,but not on the Au surface due to the spontaneous oxidation of Cu during the self-assembling process.It can be concluded that the SFG signal on the Cu surface was from copper oxide,while on the Au surface was from gold itself.The absolute phase difference between copper oxide and gold caused the relative phase difference between the surface molecules and the substrates,which led to the SFG spectral lineshape changes of the APDTC molecule.

引言
1 实验部分
2 结果与讨论
3 结论

图1 APDTC/Cu、Cu、APDTC/Au和Au的BB-SFG归一化谱图(a),APDTC粉末样品的IR和Raman谱图(b)<br/>Fig.1 Normalized BB-SFG spectra of APDTC/Cu,Cu,APDTC/Au and Au(a),and the IR and Raman spectra of APDTC powder(b)

图1 APDTC/Cu、Cu、APDTC/Au和Au的BB-SFG归一化谱图(a),APDTC粉末样品的IR和Raman谱图(b)
Fig.1 Normalized BB-SFG spectra of APDTC/Cu,Cu,APDTC/Au and Au(a),and the IR and Raman spectra of APDTC powder(b)

表1 APDTC分子C—H伸缩振动的谱峰位置及其归属[23-26]<br/>Tab.1 Peak position and assignment of C—H stretching vibrations of APDTC molecule[23-26]

表1 APDTC分子C—H伸缩振动的谱峰位置及其归属[23-26]
Tab.1 Peak position and assignment of C—H stretching vibrations of APDTC molecule[23-26]

图2 APDTC/Cu(a)和APDTC/Au(b)的BB-SFG拟合光谱<br/>Fig.2 BB-SFG fitting spectra of APDTC/Cu(a)and APDTC/Au(b)

图2 APDTC/Cu(a)和APDTC/Au(b)的BB-SFG拟合光谱
Fig.2 BB-SFG fitting spectra of APDTC/Cu(a)and APDTC/Au(b)

表2 APDTC分子共振谱峰与Au或Cu基底的相对相位<br/>Tab.2 The relative phases between the resonant peak of APDTC molecule and Au or Cu substrates

表2 APDTC分子共振谱峰与Au或Cu基底的相对相位
Tab.2 The relative phases between the resonant peak of APDTC molecule and Au or Cu substrates

图3 ODT/Cu、Cu、ODT/Au和Au的BB-SFG归一化谱图<br/>Fig.3 Normalized BB-SFG spectra of ODT/Cu,Cu,ODT/Au and Au

图3 ODT/Cu、Cu、ODT/Au和Au的BB-SFG归一化谱图
Fig.3 Normalized BB-SFG spectra of ODT/Cu,Cu,ODT/Au and Au

图4 Cu、APDTC/Cu、Au和APDTC/Au的XRD谱图<br/>Fig.4 XRD patterns of Cu,APDTC/Cu,Au and APDTC/Au

图4 Cu、APDTC/Cu、Au和APDTC/Au的XRD谱图
Fig.4 XRD patterns of Cu,APDTC/Cu,Au and APDTC/Au

图5 APDTC分子在Cu(a)和Au(b)表面的吸附构型示意图<br/>Fig.5 Illustration of adsorption configurations for APDTC on Cu(a)and Au(b)surfaces

图5 APDTC分子在Cu(a)和Au(b)表面的吸附构型示意图
Fig.5 Illustration of adsorption configurations for APDTC on Cu(a)and Au(b)surfaces

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备注

引言

1 实验部分

2 结果与讨论

3 结论

学报简介

备注

引言

1 实验部分

2 结果与讨论

3 结 论

学报简介

3 结论