Development and advances of nanoscale reference materials in China
As an integral part of nanostandardization,the development of nanoscale certified reference materials(nano-CRMs)is crucial for the healthy and sustainable development of nanotechnology and the nano-industry.The Chinese government places great importance on nanotechnology standardization and has steadily supported the advancement of this field and the construction of nanostandardization systems.Over the past three Five-Year Plans,the country has launched three nanostandard projects through the National Key Basic Research Program of China from"Nano Research Plan".In this paper,based on these three nanostandard projects,we look back at the institutionalized development history of nanoscale reference materials in China,starting from scratch.During the Eleventh Five-Year Plan,facing the difficult situation of nano-CRMs shortage in China,we laid out the development planning for urgently needed reference materials in nano-measurement,which initiated the organized R&D of nanoscale reference materials in our conuntry.After five years of efforts,the project(2006CB932600)released 39 national standard materials,covering particle size,step height,grating,specific surface area,and hardness.It alleviated the dilemma of insufficient quantity and limited variety of nanoscale reference materials/samples at that time in China.The minimum sizes of polystyrene microspheres(～80nm,GBW 12011)and nano-silica(～60nm,GBW 12027)are comparable to NIST's 60 nm polystyrene microspheres(SRM1964)and the European Union's 80 nm silica microspheres(ERM-FD101b),respectively.The series of nanoscale reference materials provided strong support for improving the accuracy and reliability of nanoscience/technology measurements in China.During the Twelfth Five-Year Plan,we further focused on the controllable preparation and traceable measurement of nanoscale reference materials/samples(2011CB932800).We systematically studied length measurement methods with different measurement principles,established a traceability chain from the meter definition national standard to the nanoscale line spacing/line width measurement,and completed the metrological traceability for the measurement of these two parameters.Similar research was conducted on the measurement of particle size.We established calibration techniques and standard measurement methods for five commonly used particle size measurement methods,providing a guarantee for the unified measurement of particle sizes in China.Besides,we also launched the development of reference materials for functional nanomaterials,such as titanium nanoparticles with photocatalytic activity,gold nanorods with plasmonic response,and quantum dots with fluorescence property.In the end,depending on the specific use of reference materials,we have formulated a classification for nanoscale reference materials at three different levels:Reference materials for nanoscale measurement,nanomaterial physicochemical characterization,and functionality evaluation.During the Thirteenth Five-Year Plan,we shifted our focus on the nano-manufacturing and nano-medical device field,as the ultimate goal of nanotechnology standardization is to promote the healthy and sustainable development of nano-enabled industry(2016YFA0200900).In this project,Tongji University leveraged its unique atomic lithography technology to lead the development of ultra-precise nanogratings with self-traceability features.This advancement has further reduced the dimensions of one-dimensional gratings in China to scales as small as 200 and 100 nm.Meanwhile,Xi'an Jiaotong University pioneered the adoption of advanced atomic layer deposition(ALD)technology on the fabrication of nanoscale steps.Four national-level step height standard materials with heights below 50 nm were developed.This achievement not only addressed the domestic gap but also positioned China at the forefront of international advancements.For nano-medical device field,two nanosilver CRMs and two gold-labeled nanosilver standard samples were released.Based on these reference materials,we have developed a normative framework for evaluating the performance of nano-medical products and have laid the groundwork for risk assessment in product applications.Through project-driven institutionalized research,we have significantly narrowed the gap in nanotechnology standardization between our country and the developed countries.Looking to the future,we will continue to promote the system construction of China's nanoscale reference materials based on the new trends in nanometrology and nano-industry.
NETL
NSTL
万方数据
维普
