Preparation And Self-assemble Of Noble Nanoparticles And Basic Rearch On Its Biochemical Sensoring Application

It is a hot issue to design and synthesize nanomaterials with controlled compositions,structures and morphologies according to the application requirements. The metalnanoparticles with tunable surface plasma resonance （SPR） were intensely attractive for theirunique optical properties and their applications in biomedicine, catalysis, electronics,communication and other fields.In this thesis, low-dimensional nanomaterials were applied in biochemical sensors, andthen the synthesis of noble nanoparticles, self-assembly process and biochemical sensingapplications were studied. Noble nanoparticles were prepared by the means of sputting. Bymeans of thermal annealing or Ostwald-ripening process, low-dimensional nanomaterialsachieve self-assembly process of efficient and cost-effective . Through the use of biologicalmacromolecular material （Crystal Violet（CV）） as a probe molecule, investigation of surfaceenhanced Raman scattering （SERS） and surface-enhanced fluorescence （SEF）, bio-chemicalsensors based on SERS and SEF was studied.In theory, noble nanoparticles sputtering mechanism, nanoparticle self-assembly process,the generating mechanism of the local surface plasma resonance （LSPR） effect, SERS andSEF effect of the noble nanoparticles are analyzed.In the experimental, noble nanoparticles were prepared by the means of sputting. Byrunning different deposition time, nanoparticles of different density and size were obtined.AFM images obtained from two sets of samples, give the opportunity to get an estimation ofthe size of each individual nanoparticle and eventually calculate the dimension distribution.By means of thermal annealing, low-dimensional nanomaterials achieve self-assemblyprocess on SiO₂ base. Scanning electron microscopy （SEM） and Raman spectroscopy wereused to characterize the self-assembly nanostructure. Then further comparison is done toresearch the difference for varying the annealing temperature. We combined with Ramanspectroscopy, Fluorescence spectroscopy and AFM pictures studing the impact of theprocessing time, the substrates and the concentration of treatment solution onOstwald-ripening self-assembly process. In order to search the application of self-assemblenanostructure with biochemical sensor, we did a lot of preliminary exploration, trying to modify the CV on nanostructure, named biochemical sensor which based on the effect ofSERS or SEF. Test the difference of SERS and SEF spectrum between different sizes anddensity of nanoparticles.In this paper, we explore the nanoparticles self-assembly manufacturing technology oflow-cost, large-area. The basis of theories and key technologies are provided to realize theengineering manufacture of low-dimensional nanostructures. By adjusting the key parametersof the nanostructures, the optimization of biochemical sensitivity of self-assembly nanostructure is achieved.