V. Rana, Jeevitesh K. Rajput, T. K. Pathak, P. K. Pal, L. P. Purohit
In the present work, fixed Al (2.5 wt%) doped zinc oxide (ZnO) thin films are fabricated at different radio frequency (RF) power on indium doped tin oxide‐coated polyethylene terephthalate substrate by sputtering techniques. From the X‐ray diffraction (XRD) results it has been observed that all thin films have polycrystalline nature with hexagonal structure. Stress of thin film calculated from XRD measurement is increased from −0.10 × 109 to 0.23 × 109 N m−2 with increase in RF sputtering power. The morphology analyzed by field electron microscopy is observed as irregular sphere for all samples. The estimated values of thickness are 440, 870, 913, and 1086 nm for the films grown at RF sputtering powers 130, 140, 150, and 160 W, respectively. On increasing the RF power from 130 to 160 W, the optical bandgap is decreased from 3.59 to 3.48 eV. The highest conductivity obtained is 2.43 × 102 S m−1 for the sample grown at sputtering power 160 W. The study reveals that there is an impact of sputtering power on the various properties of thin films grown on flexible substrates and these films have wide applications in flexible electro‐optical applications.
在本研究中,采用溅射技术在掺杂铟氧化锡涂层的聚对苯二甲酸乙二醇酯衬底上以不同的射频(RF)功率制备了Al (2.5 wt%)掺杂氧化锌(ZnO)的固定薄膜。X射线衍射(XRD)结果表明,所有薄膜都具有六边形结构的多晶性质。随着射频溅射功率的增加,薄膜的应力从−0.10 × 109 N m−2增加到0.23 × 109 N m−2。通过场电子显微镜观察,所有样品的形貌均为不规则球体。在130、140、150和160 W的射频溅射功率下生长的薄膜厚度的估计值分别为440、870、913和1086 nm。当射频功率从130 W增加到160 W时,光带隙从3.59 eV减小到3.48 eV。当溅射功率为160 W时,样品的最高电导率为2.43 × 102 S m−1。研究表明,溅射功率对在柔性衬底上生长的薄膜的各种性能有影响,这些薄膜在柔性电光应用中具有广泛的应用前景。
{"title":"Impact of RF Sputtering Power on AZO Thin Films for Flexible Electro‐Optical Applications","authors":"V. Rana, Jeevitesh K. Rajput, T. K. Pathak, P. K. Pal, L. P. Purohit","doi":"10.1002/crat.202000144","DOIUrl":"https://doi.org/10.1002/crat.202000144","url":null,"abstract":"In the present work, fixed Al (2.5 wt%) doped zinc oxide (ZnO) thin films are fabricated at different radio frequency (RF) power on indium doped tin oxide‐coated polyethylene terephthalate substrate by sputtering techniques. From the X‐ray diffraction (XRD) results it has been observed that all thin films have polycrystalline nature with hexagonal structure. Stress of thin film calculated from XRD measurement is increased from −0.10 × 109 to 0.23 × 109 N m−2 with increase in RF sputtering power. The morphology analyzed by field electron microscopy is observed as irregular sphere for all samples. The estimated values of thickness are 440, 870, 913, and 1086 nm for the films grown at RF sputtering powers 130, 140, 150, and 160 W, respectively. On increasing the RF power from 130 to 160 W, the optical bandgap is decreased from 3.59 to 3.48 eV. The highest conductivity obtained is 2.43 × 102 S m−1 for the sample grown at sputtering power 160 W. The study reveals that there is an impact of sputtering power on the various properties of thin films grown on flexible substrates and these films have wide applications in flexible electro‐optical applications.","PeriodicalId":10797,"journal":{"name":"Crystal Research and Technology","volume":"8 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90038009","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tungsten disulfide (WS2) as a 2D layered material shows good application in the field of electrocatalysis due to its unique 2D structure, excellent electronic properties, and catalytic activity. However, the electrocatalytic performance of bulk WS2 materials is limited due to the lack of active sites. Hence, a few layers of WS2 nanosheets are prepared by a simple method of lithium (Li)‐ion intercalation exfoliation, and enhanced electrocatalytic hydrogen evolution performance is demonstrated compared to bulk WS2. This method can not only realize the large‐scale preparation of WS2 nanosheets, but also the obtained WS2 nanosheets have a larger lateral size, a good lattice structure, and no chemical impurities remain. Most importantly, it is realized that the reduction in the thickness of WS2 nanosheets will generate additional active sites from the ultrathin planar structure, thereby improving electrocatalytic activity. The exfoliated WS2 nanosheets show a smaller overpotential compared to the bulk WS2, the overpotential is about 320 mV at 10 mA cm–2. This work shows that Li‐ion intercalation exfoliated method is an efficient strategy to prepare 2D nanosheets materials and effectively improve its electrocatalytic performance.
二硫化钨(WS2)作为一种二维层状材料,由于其独特的二维结构、优异的电子性能和催化活性,在电催化领域具有良好的应用前景。然而,由于缺乏活性位点,块状WS2材料的电催化性能受到限制。因此,通过简单的锂离子嵌入剥离方法制备了几层WS2纳米片,与大块WS2相比,电催化析氢性能得到了增强。该方法不仅可以实现WS2纳米片的大规模制备,而且得到的WS2纳米片横向尺寸较大,晶格结构良好,无化学杂质残留。最重要的是,我们认识到WS2纳米片厚度的减小将从超薄的平面结构中产生额外的活性位点,从而提高电催化活性。与本体WS2相比,剥离后的WS2纳米片显示出较小的过电位,在10 mA cm-2下的过电位约为320 mV。研究表明,锂离子插层剥离法是制备二维纳米片材料并有效提高其电催化性能的有效方法。
{"title":"Li‐Ion Intercalated Exfoliated WS2 Nanosheets with Enhanced Electrocatalytic Hydrogen Evolution Performance","authors":"L. Tian, H. Qiao, Zongyu Huang, X. Qi","doi":"10.1002/crat.202000165","DOIUrl":"https://doi.org/10.1002/crat.202000165","url":null,"abstract":"Tungsten disulfide (WS2) as a 2D layered material shows good application in the field of electrocatalysis due to its unique 2D structure, excellent electronic properties, and catalytic activity. However, the electrocatalytic performance of bulk WS2 materials is limited due to the lack of active sites. Hence, a few layers of WS2 nanosheets are prepared by a simple method of lithium (Li)‐ion intercalation exfoliation, and enhanced electrocatalytic hydrogen evolution performance is demonstrated compared to bulk WS2. This method can not only realize the large‐scale preparation of WS2 nanosheets, but also the obtained WS2 nanosheets have a larger lateral size, a good lattice structure, and no chemical impurities remain. Most importantly, it is realized that the reduction in the thickness of WS2 nanosheets will generate additional active sites from the ultrathin planar structure, thereby improving electrocatalytic activity. The exfoliated WS2 nanosheets show a smaller overpotential compared to the bulk WS2, the overpotential is about 320 mV at 10 mA cm–2. This work shows that Li‐ion intercalation exfoliated method is an efficient strategy to prepare 2D nanosheets materials and effectively improve its electrocatalytic performance.","PeriodicalId":10797,"journal":{"name":"Crystal Research and Technology","volume":"82 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75679223","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Masthead: Crystal Research and Technology 3'2021","authors":"","doi":"10.1002/crat.202170015","DOIUrl":"https://doi.org/10.1002/crat.202170015","url":null,"abstract":"","PeriodicalId":10797,"journal":{"name":"Crystal Research and Technology","volume":"7 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84906344","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
KTiOPO4 (KTP) crystals are prepared by the top‐seeded solution growth method. Effects of space irradiation on KTP crystal structure have been investigated using Space Tribology in‐situ Analysis System: KTP crystal (001) surfaces were irradiated by atomic oxygen (AO) and electron (EL), and the electronic structure was analyzed using X‐ray photoelectron spectroscopy (XPS). The AO has strong oxidizing property which results in decreases in the intensity of C 1s peak. The content of P increases after AO/EL irradiation, while the content of Ti decreases after AO irradiation. The reduced ΔBE (O─P) shows stronger ionicity of P─O bonds after AO/EL irradiation compared with pristine KTP crystal. The deconvolution of O 1s photoemission line reveals that peaks at 530.8–531.0 and 530.1 eV are assigned to O─P and O─Ti bonds, respectively. Additionally, variations in the trend of O─P bond and O─Ti bond contents are resembled to that of P and Ti after AO/EL irradiation.
{"title":"Effect of Atomic Oxygen and Electron Irradiation on the Electronic Structure of KTiOPO4 Crystal","authors":"Jian Liu, Yan Lu, Junying Hao","doi":"10.1002/crat.202000175","DOIUrl":"https://doi.org/10.1002/crat.202000175","url":null,"abstract":"KTiOPO4 (KTP) crystals are prepared by the top‐seeded solution growth method. Effects of space irradiation on KTP crystal structure have been investigated using Space Tribology in‐situ Analysis System: KTP crystal (001) surfaces were irradiated by atomic oxygen (AO) and electron (EL), and the electronic structure was analyzed using X‐ray photoelectron spectroscopy (XPS). The AO has strong oxidizing property which results in decreases in the intensity of C 1s peak. The content of P increases after AO/EL irradiation, while the content of Ti decreases after AO irradiation. The reduced ΔBE (O─P) shows stronger ionicity of P─O bonds after AO/EL irradiation compared with pristine KTP crystal. The deconvolution of O 1s photoemission line reveals that peaks at 530.8–531.0 and 530.1 eV are assigned to O─P and O─Ti bonds, respectively. Additionally, variations in the trend of O─P bond and O─Ti bond contents are resembled to that of P and Ti after AO/EL irradiation.","PeriodicalId":10797,"journal":{"name":"Crystal Research and Technology","volume":"114 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73934797","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The cocrystal of ammonium dinitramide (ADN)/1,4,7,10,13,16‐hexaoxacyclooctadecane (18‐Crown‐6) has effectively reduced the hygroscopicity of ADN. In order to understand the effect of solvent on the crystal growth, the interfacial models of ADN/18‐Crown‐6–ethanol are built and simulated by the molecular dynamics (MD) method at different temperatures (293–323 K, 10 K intervals). The energy, mass density, radial distribution function, and diffusion capacity of solvent are analyzed. The modified attachment energy (MAE) model is employed to study the solvent effect on cocrystal morphology. Results of MD simulation show that ADN/18‐Crown‐6 cocrystal has four important growth surfaces in vacuum, i.e., (2 0 0), (0 0 2), (1 1 0), and (2 0 −2). The binding energy of cocrystal and the absorbed energy of cocrystal–solvent are larger at 293 K than other temperatures. Hydrogen bonding interactions are formed between ADN/18‐Crown‐6 and solvent. More ethanol molecules adsorb on the crystal surface at lower temperatures, and hence the interaction between cocrystal and solvent is stronger. The morphology of ADN/18‐Crown‐6 cocrystal is different at various temperatures. The predicted morphology at 303 K is consistent with experimental shape. Moreover, cocrystal morphology at 293 K is a sphere‐like shape, which may reduce the hygroscopicity of ADN/18‐Crown‐6 cocrystal.
{"title":"Theoretical Study on the Effect of Solvent Behavior on Ammonium Dinitramide (ADN)/1,4,7,10,13,16‐Hexaoxacyclooctadecane (18‐Crown‐6) Cocrystal Growth Morphology at Different Temperatures","authors":"Honglu Xie, Rui‐jun Gou, Shuhai Zhang","doi":"10.1002/crat.202000203","DOIUrl":"https://doi.org/10.1002/crat.202000203","url":null,"abstract":"The cocrystal of ammonium dinitramide (ADN)/1,4,7,10,13,16‐hexaoxacyclooctadecane (18‐Crown‐6) has effectively reduced the hygroscopicity of ADN. In order to understand the effect of solvent on the crystal growth, the interfacial models of ADN/18‐Crown‐6–ethanol are built and simulated by the molecular dynamics (MD) method at different temperatures (293–323 K, 10 K intervals). The energy, mass density, radial distribution function, and diffusion capacity of solvent are analyzed. The modified attachment energy (MAE) model is employed to study the solvent effect on cocrystal morphology. Results of MD simulation show that ADN/18‐Crown‐6 cocrystal has four important growth surfaces in vacuum, i.e., (2 0 0), (0 0 2), (1 1 0), and (2 0 −2). The binding energy of cocrystal and the absorbed energy of cocrystal–solvent are larger at 293 K than other temperatures. Hydrogen bonding interactions are formed between ADN/18‐Crown‐6 and solvent. More ethanol molecules adsorb on the crystal surface at lower temperatures, and hence the interaction between cocrystal and solvent is stronger. The morphology of ADN/18‐Crown‐6 cocrystal is different at various temperatures. The predicted morphology at 303 K is consistent with experimental shape. Moreover, cocrystal morphology at 293 K is a sphere‐like shape, which may reduce the hygroscopicity of ADN/18‐Crown‐6 cocrystal.","PeriodicalId":10797,"journal":{"name":"Crystal Research and Technology","volume":"32 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89756740","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jesús Chávez‐Reyes, Eduardo Hernández-Cuellar, H. A. González-Ponce, M. G. Rodríguez
In vitro synthesis of uric acid crystals provides an important source to study the process of crystal formation and to understand how the deposition of these crystals induces disease; nevertheless, the described methodologies for the synthesis of uric acid crystals are time‐consuming, depend on the use of high volumes, and the time scale precludes the kinetics study of the crystal growth. In the present work, it is described a fast method for the synthesis of anhydrous uric acid (AUA) crystals using microvolumes, and the crystal growth kinetics is characterized by light field microscopy using nonlinear adjustment. In addition, a crystal morphological characterization by scanning electron microscopy and X‐ray diffraction is made, disclosing that the AUA crystals are arranged in stacked layer sheets with an orthorhombic‐like shape. These results help to understand the phenomenon of crystallization of uric acid, which is a trigger event on the development of uric acid nephrolithiasis.
{"title":"Growth Kinetics Analysis and Morphological Characterization by Electron Microscopy of Anhydrous Uric Acid Crystals","authors":"Jesús Chávez‐Reyes, Eduardo Hernández-Cuellar, H. A. González-Ponce, M. G. Rodríguez","doi":"10.1002/crat.202000164","DOIUrl":"https://doi.org/10.1002/crat.202000164","url":null,"abstract":"In vitro synthesis of uric acid crystals provides an important source to study the process of crystal formation and to understand how the deposition of these crystals induces disease; nevertheless, the described methodologies for the synthesis of uric acid crystals are time‐consuming, depend on the use of high volumes, and the time scale precludes the kinetics study of the crystal growth. In the present work, it is described a fast method for the synthesis of anhydrous uric acid (AUA) crystals using microvolumes, and the crystal growth kinetics is characterized by light field microscopy using nonlinear adjustment. In addition, a crystal morphological characterization by scanning electron microscopy and X‐ray diffraction is made, disclosing that the AUA crystals are arranged in stacked layer sheets with an orthorhombic‐like shape. These results help to understand the phenomenon of crystallization of uric acid, which is a trigger event on the development of uric acid nephrolithiasis.","PeriodicalId":10797,"journal":{"name":"Crystal Research and Technology","volume":"18 4 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80690114","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Past studies report that nucleation promotion is induced by quick heating of microwave in nanoparticle synthesis. However, how the nucleation promotion quantitatively affects particle number density is still unclear. In this study, the number density is predicted using bubble size profiles measured under microwave irradiation. This idea is based on a finding that the maximum bubble size during the irradiation is closely related to the particle number density due to homogeneous distribution of microwave absorbance energy to the particles. The results indicate that when solute concentration or anti‐solvent concentration is higher, the particle number density also increases due to the nucleation promotion caused by microwave quick heating. This new approach can be expected as an innovative and rapid method for quantitative estimation of particle number density in microwave‐assisted nanoparticle manufacture.
{"title":"Prediction of Particle Number Density in Suspension by Measuring the Sizes of Bubbles Generated During Microwave Irradiation","authors":"Y. Asakuma, A. Shibatani, Haruka Kan, A. Saptoro","doi":"10.1002/crat.202000160","DOIUrl":"https://doi.org/10.1002/crat.202000160","url":null,"abstract":"Past studies report that nucleation promotion is induced by quick heating of microwave in nanoparticle synthesis. However, how the nucleation promotion quantitatively affects particle number density is still unclear. In this study, the number density is predicted using bubble size profiles measured under microwave irradiation. This idea is based on a finding that the maximum bubble size during the irradiation is closely related to the particle number density due to homogeneous distribution of microwave absorbance energy to the particles. The results indicate that when solute concentration or anti‐solvent concentration is higher, the particle number density also increases due to the nucleation promotion caused by microwave quick heating. This new approach can be expected as an innovative and rapid method for quantitative estimation of particle number density in microwave‐assisted nanoparticle manufacture.","PeriodicalId":10797,"journal":{"name":"Crystal Research and Technology","volume":"67 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73249216","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Takashi Tsukasaki, Ren Hiyoshi, M. Fujita, T. Makimoto
The photoluminescence (PL) mechanism is discussed for heavily Si‐doped GaAsN, and the evaluation method of electron effective mass (me*) is proposed using its PL peak energy. PL peak energy monotonically decreases as increasing temperature, so the S‐shape characteristic is vanished for this heavily Si‐doped GaAsN as opposed to moderately Si‐doped GaAsN. This result shows that the dominant PL process is an optical transition from the Fermi energy to the top of valence band independent of temperature for this heavily Si‐doped GaAsN, as with degenerate n‐type GaAs. Because PL peak energy is expressed by the sum of bandgap energy, the increased energy of the Burstein–Moss effect, and the decreased energy of the bandgap narrowing, me* is calculated to be 0.098 m0 for this heavily Si‐doped GaAsN with nitrogen composition of 0.6%, where m0 is the electron mass. This result agrees well with previous studies, meaning that the method for estimation of me is effective for dilute GaAsN.
{"title":"Photoluminescence Mechanism in Heavily Si‐Doped GaAsN","authors":"Takashi Tsukasaki, Ren Hiyoshi, M. Fujita, T. Makimoto","doi":"10.1002/crat.202000143","DOIUrl":"https://doi.org/10.1002/crat.202000143","url":null,"abstract":"The photoluminescence (PL) mechanism is discussed for heavily Si‐doped GaAsN, and the evaluation method of electron effective mass (me*) is proposed using its PL peak energy. PL peak energy monotonically decreases as increasing temperature, so the S‐shape characteristic is vanished for this heavily Si‐doped GaAsN as opposed to moderately Si‐doped GaAsN. This result shows that the dominant PL process is an optical transition from the Fermi energy to the top of valence band independent of temperature for this heavily Si‐doped GaAsN, as with degenerate n‐type GaAs. Because PL peak energy is expressed by the sum of bandgap energy, the increased energy of the Burstein–Moss effect, and the decreased energy of the bandgap narrowing, me* is calculated to be 0.098 m0 for this heavily Si‐doped GaAsN with nitrogen composition of 0.6%, where m0 is the electron mass. This result agrees well with previous studies, meaning that the method for estimation of me is effective for dilute GaAsN.","PeriodicalId":10797,"journal":{"name":"Crystal Research and Technology","volume":"23 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84962645","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Rare earth ions Er3+, La3+, and Y3+ have been introduced into the lattice of CdS nanobelts (NBs) to modulate its radiative recombination rate (RRR) during photoluminescence (PL) process. It is found that these ions have different quenching effects on the RRRs of direct interband transition and defect related transition. Only the former is greatly reduced through Er3+ doping, however, both of them are suppressed to a certain extent by La3+ and Y3+ doping. It is valuable that specific solid color luminescence can be realized through well‐chosen rare earth ions.
{"title":"Modulation on Radiative Recombination Rate of CdS Nanobelts by Selective Rare Earth Ions","authors":"Xu Ji, Shuang Cheng","doi":"10.1002/crat.202000170","DOIUrl":"https://doi.org/10.1002/crat.202000170","url":null,"abstract":"Rare earth ions Er3+, La3+, and Y3+ have been introduced into the lattice of CdS nanobelts (NBs) to modulate its radiative recombination rate (RRR) during photoluminescence (PL) process. It is found that these ions have different quenching effects on the RRRs of direct interband transition and defect related transition. Only the former is greatly reduced through Er3+ doping, however, both of them are suppressed to a certain extent by La3+ and Y3+ doping. It is valuable that specific solid color luminescence can be realized through well‐chosen rare earth ions.","PeriodicalId":10797,"journal":{"name":"Crystal Research and Technology","volume":"48 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80460098","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Shujie Liu, Bidong Wu, Jia-ni Xie, Zhimin Li, Chongwei An, Jingyu Wang, Xiaodong Li
Highly efficient design for the formulation of explosives is desired for accelerating the development of energetic materials. These investigations are focused on the preparation of the compounds 3,3′‐diamino‐4,4′‐azoxyfurazan (DAAF) and 1,1‐diamino‐2,2‐dinitroethylene (FOX‐7). DAAF/FOX‐7 microspheres are prepared via the self‐assembly method using different mass ratios of DAAF and FOX‐7. Materials Studio is used to analyze the intermolecular binding energy (Ebind) of the composite system. DAAF/FOX‐7 with a mass ratio of 90:10 shows a higher Ebind (183.24 kJ mol−1) and peak temperature at the heating rate of 0 °C min−1 (266.2 °C) than DAAF/FOX‐7 with a mass ratio of 70:30 and DAAF/FOX‐7 with a mass ratio of 80:20; this indicates that DAAF/FOX‐7 (90:10) shows better thermal stability. EXPLO5 is used to analyze the detonation velocity of the composite system, and the detonation velocity of DAAF/FOX‐7 microspheres increase by 0.5 km s−1 compared to that of DAAF. The characteristic drop height of impact sensitivity is more than 100 cm, and this demonstrates that the microspheres exhibit good safety performance. The morphology, crystal structure, thermal decomposition property, and impact sensitivity of the microspheres are investigated and compared. X‐ray diffraction and Fourier transform infrared spectroscopy results indicate that the structure of the DAAF/FOX‐7 composite is not changed compared to that of the raw material.
{"title":"Self‐Assembly Method for Insensitive DAAF/FOX‐7 Composite Crystals with Microspheres Structure","authors":"Shujie Liu, Bidong Wu, Jia-ni Xie, Zhimin Li, Chongwei An, Jingyu Wang, Xiaodong Li","doi":"10.1002/crat.202000194","DOIUrl":"https://doi.org/10.1002/crat.202000194","url":null,"abstract":"Highly efficient design for the formulation of explosives is desired for accelerating the development of energetic materials. These investigations are focused on the preparation of the compounds 3,3′‐diamino‐4,4′‐azoxyfurazan (DAAF) and 1,1‐diamino‐2,2‐dinitroethylene (FOX‐7). DAAF/FOX‐7 microspheres are prepared via the self‐assembly method using different mass ratios of DAAF and FOX‐7. Materials Studio is used to analyze the intermolecular binding energy (Ebind) of the composite system. DAAF/FOX‐7 with a mass ratio of 90:10 shows a higher Ebind (183.24 kJ mol−1) and peak temperature at the heating rate of 0 °C min−1 (266.2 °C) than DAAF/FOX‐7 with a mass ratio of 70:30 and DAAF/FOX‐7 with a mass ratio of 80:20; this indicates that DAAF/FOX‐7 (90:10) shows better thermal stability. EXPLO5 is used to analyze the detonation velocity of the composite system, and the detonation velocity of DAAF/FOX‐7 microspheres increase by 0.5 km s−1 compared to that of DAAF. The characteristic drop height of impact sensitivity is more than 100 cm, and this demonstrates that the microspheres exhibit good safety performance. The morphology, crystal structure, thermal decomposition property, and impact sensitivity of the microspheres are investigated and compared. X‐ray diffraction and Fourier transform infrared spectroscopy results indicate that the structure of the DAAF/FOX‐7 composite is not changed compared to that of the raw material.","PeriodicalId":10797,"journal":{"name":"Crystal Research and Technology","volume":"7 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82204499","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}