Application Of Ion Beam Technology Research Articles

Recent Progress in the Application of Ion Beam Technology in the Modification and Fabrication of Nanostructured Energy Materials.

The development of green, renewable energy conversion and storage systems is an urgent task to address the energy crisis and environmental issues in the future. To achieve high performance, stable, and safe operation of energy conversion and storage systems, energy materials need to be modified and fabricated through rationalization. Among various modification and fabrication strategies, ion beam technology has been widely used to introduce various defects/dopants into energy materials and fabricate various nanostructures, where the structure, composition, and property of prefabricated materials can be further accurately tailored to achieve better performance. In this paper, we review the recent progress in the application of ion beam technology in material modification and fabrication, focusing on nanostructured energy materials for energy conversion and storage including photo- (electro-) water splitting, batteries (solar cells, fuel cells, and metal-ion batteries), supercapacitors, thermoelectrics, and hydrogen storage. This review first provides a brief basic overview of ion beam technology and describes the classification and technological advantages of ion beam technology in the modification and fabrication of materials. Then, modification of energy materials by ion beams is reviewed mainly concerning doping and defect introduction. Fabrication of energy materials is also discussed mainly in terms of heterojunctions, nanoparticles, nanocavities, and other nanostructures. In particular, we emphasize the advantages of ion beam technology in improving the performance of energy materials. Finally, we point out our understanding of challenges and future perspectives in applying ion beam technology for the modification and fabrication of energy materials.

Application of ion beam technology in (photo)electrocatalytic materials for renewable energy

The development of environmentally friendly, efficient, and universal access renewable energy technology is the key to achieve the goal of sustainable development. (Photo)electrochemical energy storage and conversion technology is an important part. Therefore, to realize the practical application of (photo)electrochemical energy technology, nanostructured catalytic materials need to be reasonably designed, synthesized, and modified. Ion beam technology is a powerful and versatile physical modification method. Modification of various catalytic materials from the surface to interface and thin films can be realized by controlling the species, energy, and fluence of implanted ions. Ion beam technology has its unique advantages, including its compulsivity of element doping and its high controllability, accuracy, and repeatability. It can realize arbitrary element doping and defect control of almost any material and finely control its concentration. This makes it possible for the ion beam technology to adapt to the modification requirements of catalytic materials to tailor the electronic structure, interface structure, and morphology of the materials more finely. Besides, a variety of strategies for material design can be realized using ion beams, including element doping, defect control, heterostructure construction, and micro/nanostructure formation, which may bring novel changes in catalytic materials. In this Review, we briefly introduce the principle of ion beam technology and introduce various ion beam technologies that can be applied to different catalytic material modification applications. We systematically review the research progress on the application of ion beam technology in photocatalytic, photoelectrocatalytic, and electrocatalytic materials for water splitting including bandgap engineering, defect engineering, heterostructure formation through ion doping, ion irradiation, ion sputtering, and their combined effects. The applications of ion beam technology on modification of fuel oxidation reaction and oxygen reduction reaction electrocatalysts for fuel cells are also introduced. The advantages of ion beam technology in the modification of catalytic materials are summarized. Several promising topics are proposed to look forward to the future development of ion beam technology in the field of catalytic materials.

Generating Sub-nanometer Pores in Single-Layer MoS2 by Heavy-Ion Bombardment for Gas Separation: A Theoretical Perspective.

Single-layer molybdenum disulfide (MoS2) filters with nanometer-size pores have attracted great attention recently due to their promising performance for membrane separation. Generating nanopores in MoS2 controllably, however, is still a challenging task, which greatly limits the real application of MoS2 filters. In this work, the pore forming process in single-layer MoS2 by heavy-ion bombardment was investigated in detail using molecular dynamics simulations. We found that pores with sub-nanometer size (0.6-1.2 nm) can be created in the MoS2 sheet by single-ion bombardment, with a probability as high as 0.8 pores per incident ion. The size and shape of the nanopore can be tuned controllably by adjusting bombardment parameters. Furthermore, the performance of the MoS2 filter with these sub-nanometer-size pores for separation of He, Ne, H2, Ar, and Kr gases was evaluated by density functional theory-based first-principles calculations. The MoS2 filter was found to show much higher selectivity for separating H2/He and He/Ne than that reported for graphene and other membranes. Such high selectivity was attributed to the interaction between gases and the charged edge of pores in MoS2. Our results suggest the potential application of ion beam technology in single-layer MoS2 for membrane separation.

Application of ion beam technology in modification of photoelectrode

Semiconductor-based photoelectrolysis for water splitting to produce hydrogen and oxygen is a simple, relatively cheap and reliable way for energy utilization. Therefore, developing photoelectrode materials with high solar-to-hydrogen (STH) efficiency has become a hotspot in the field of material science. Many semiconductor-based photoelectrolysis suffer from the lack of visible light response and low charge separation efficiency resulting in low photoelectrocatalytic activity. It is particularly important to developing modified photoelectrode materials. Ion beam technology, as an important semiconductor modification technology, has been generally used to modify the electronic property of silicon. It has great potential application in modification of photoelectrode materials. Comparing with traditional modification method, ion beam technology has many advantages, such as good repeatability and controllability. Ion beam technology is an effective method for doping. Various ion species can be doped into photoelectrode materials. The ion implantation process could ensure the uniformity and purity of the introduced elements in materials. Doped ions can be highly dispersed and present at the lattice positions deeply inside the film. Basing on the works of our and other research groups, this review briefly introduces the advantages, the recent progress, and the current issues of application of ion beam technology in modifying photoelectrode materials. Ion beam technology has been used to effectively improve visible light absorption of many photoelectrode materials. TiO 2 doping through metal ion implantation has been studied since 1998. Various metal ion implantations have been found to be effective in improving material’s visible light response. Compared with metal ion implantation, only few examples of nonmetal implantation are known. Since 2005, N ion implantation was reported to be effective to improve photoelectrochemical (PEC) properties of TiO 2 , ZnO, WO 3 . Ion implantation is proven to be effective and reliable method of doping. In addition, a gradient distribution of dopants along the vertical direction of materials would be formed. The gradient distributed dopants not only enhance the visible light absorption, but also introduce a homojunction which efficiently drives photo-induced electrons and holes separation and transfers. Ion implantation introduces lots of defects into materials. The defects always are known as recombination sites of electrons and holes. Post-implantation thermal annealing process is critical for PEC performance by eliminating partial defects. However, defects introduced by ion implantation are controllable. On the one hand, by low energy ion irradiation, surface defect has formed under control in shallow zone of photoelectrode. Through defect engineering, the electronic structure of many semiconductors can be modified. An impressive promotion of electrical conductivity and more exposed of active sites can lead to remarkable enhancements in photoelectrocatalytic performance. On the other hand, by high fluence beam irradiation combination with thermal annealing, the irradiation damage can be used to form nanostructure like nanorods. Up to now, the application of ion beam technology in modifying photoelectrode materials is still at the comparatively primary stage. In order to achieve high performance photoelectrochemical water splitting using ion beam technology, more attention should be paid to the more precise control over the dopants and defects. A large number of more systematic and in-depth researches should be carried out.

Effects of low-energy N+-beam implantation on root growth in Arabidopsis seedlings

The effects of ion implantation on the morphology changes and biological responses of plants are dependent on implantation doses. Previous studies mainly focus on the application of ion-beam technology in genetic mutation. Our knowledge regarding the mechanism underlying the plant growth inhibition induced by ion implantation remains limited. In this study, we explore the responses of root growth to low-energy N+-beam implantation using implanted Arabidopsis seeds. Our results showed that the root and root tip length were obviously reduced by implantation with large doses of low-energy N+ beam. The analysis of confocal images showed that ion implantation reduced the cell viability and cell division activity in root meristem. The production rate of superoxide radical (O2•-) and contents of hydrogen peroxide (H2O2) in roots under ion implantation were markedly higher than those of controls. Transcriptional expression analysis of selected genes revealed that Arabidopsis RBOH genes associated with reactive oxygen species (ROS) production were significantly up-regulated in roots in response to ion implantation. The activities of antioxidant enzymes were also induced by ion implantation. Moreover, ROS scavenging obviously enhanced cell viability and cell division in response to ion implantation and alleviated the root growth inhibition of the implanted seedlings. Our results suggest that the overproduction of ROS induced by ion implantation is involved in the inhibitory effect of low-energy ion beam on root growth by affecting the cell viability and cell division of root meristem in Arabidopsis seedlings.

Survival of mammalian cells under high vacuum condition for ion bombardment

An ion beam has been used to irradiate various organisms and its effects have been studied. Because of the poor tolerance that mammalian cells have for vacuum, such studies have not been carried out on living mammalian cells until now. However, this work is important both for elucidating the mechanism of mutation in response to low-energy ions and in exploring possible new applications of ion beam technology. The current paper describes an investigation of the survival of mammalian cells (the A L cell line) in a high-vacuum chamber in preparation for ion bombardment studies. The ion beam facility is described and the actual vacuum profile that the cells endured in the target chamber is reported. Cells were damaged immediately following vacuum exposure; the injury was characterized by alteration of the membrane permeability, loss of firm adhesion to the dish, and increased fragility. Three cryoprotective agents were tested (glycerol, propylene glycol, and trehalose) and of these, glycerol showed the highest potency for protecting cells against vacuum stress. This was revealed by an increase in the cell survival level from <1 to >10% with a glycerol concentration of 15 and 20%. Two glycerol-based protocols were investigated (freezing-vacuum vs. non-freezing-vacuum), but there was no significant difference ( P > 0.1) in their ability to improve cell survival, the values being 10.31 ± 4.5 and 12.7 ± 3.37%, respectively with 20% glycerol concentration. These cells had a normal growth capability, and also retained integrity of the cell surface antigen CD59. These initial experiments indicate that mammalian cells can withstand vacuum to the degree that is needed to study the effect of the ion beam. In addition to the improvements made in this study, other factors are discussed that may increase the survival of mammalian cells exposed to a vacuum in future studies.

Application of Ion Beam Technology to Precise Sectioning of Solids

Application of Ion Beam Technology to Precise Sectioning of Solids