MATERIALS TECHNOLOGY
·
2020
·
IF 1.738
Binggong Yan,Shaoning Lin,Lei Kang,Xuan Song,Zhao Tian,Kaiyong Jiang
Laser annealing is used for preparation of LiMn2O4. The electrochemical characterisation shows that the cycle performance of spinel LiMn2O4 is dependent on the power of the laser and the amount of lithium excess. X-ray diffraction is used to study the phase evolution of laser-annealed LiMn2O4. The morphology of LiMn2O4 particles is observed by scanning electron microscope. Electrochemical tests show that the initial capacity of the laser-annealed LiMn2O4 is less than the untreated LiMn2O4, but the cycle performance improved noticeably.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Physical Chemistry C
·
2022
·
IF 4.177
Yunfeng Bai,Yan Yang,Yawen Deng,Suihu Dang,Zelong He,Ziwen Zhou,Lu Liu
Rare-earth-ion-doped nanocrystals have low quantum conversion efficiency due to their high surface-to-volume ratios and many surface defects, which induce fluorescence quenching. We propose a laser annealing strategy that uses a 974.5 nm laser with a high power density to heat Er3+-doped Y2O3 nanocrystals for several seconds. As a result, the upconversion of Er3+-doped Y2O3 nanocrystals is enhanced obviously after laser annealing: the green emission is enhanced by 90 times and red emission by 24 times. The main reason for the upconversion enhancement is the ultrahigh temperature caused by laser annealing, which increases the grain size and reduces the surface defects. It is an encouraging result, and laser annealing is suitable for various rare-earth-ion-doped oxide nanoparticles. Then, the strong upconversion is applied to measure temperature. After laser annealing, the highly improved fluorescence efficiency decreases the required excitation power density. The thermal effect of excitation light is negligible when the excitation power density is less than 0.13 W/mm2. The thermally coupled levels of I538/I563 and nonthermally coupled levels of I661/I800 are studied for thermometry. The experimental results show that I661/I800 has high absolute sensitivity than I538/I563 at a temperature below 400 K. Rate equations and multiphonon transitions are applied to explain the relationship between the nonthermally coupled fluorescence intensity ratio and temperature. It is instructive for the design of new temperature sensors.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
OPTICAL MATERIALS
·
2022
·
IF 3.754
Yawen Deng,Yan Yang,Shuai Zhao,Jiahao Lin,Jing Gong,Yaru He,Xiaojiang Long,Suihu Dang,Yunfeng Bai
The phosphors synthesize by the sol-gel method show low cost and good homogeneity, but it also requires furnace annealing at high-temperatures. This report uses a 980 nm laser annealing strategy to replace the furnace annealing in the sol-gel combustion synthesis . The fast laser annealing can improve the preparation efficiency of rare earth doped phosphor. Er 3+ /Li + co-doped Y 2 O 3 nanocrystals are synthesized by laser annealing strategy. The structures and spectral properties of the phosphors prepared by laser annealing are studied. The phosphors prepared by laser annealing have the same crystal structure and spectral properties as those organized by furnace annealing. In addition, phosphors can be heated into crystals using a high-power 980 nm laser. Under 980 nm excitation, the crystal prepared by laser annealing shows a much stronger fluorescence intensity than phosphors.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
SYNTHETIC METALS
·
2012
·
IF 1.829
Xiaoyan Du,Dan He,Zuo Xiao,Liming Ding
Inverted polymer solar cells with a configuration of ITO/ZnO/PBDTTT-C:PC 71 BM/MoO 3 /Ag were fabricated and a power conversion efficiency of 6.64% was achieved under AM 1.5G irradiation (89 mW/cm 2 ). The function of UV light was systematically investigated by tracking the changes of the device performance for 212 min under continuous illumination with or without UV light. We found that UV light plays a decisive role not only in the photo-annealing step, leading to a remarkable increase of PCE by increasing ZnO conductance, but also in the photo-bleaching step, causing slow degradation of solar cells through photo-oxidation of the conjugated polymer.
研究领域:
材料科学
·
光伏技术
·
光化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2023
·
IF 9.5
Linrong Zhang,Li Wang,Shunhao He,Chengcheng Zhu,Zhongyan Gong,Yulong Zhang,Junjie Wang,Liuyingzi Yu,Kun Gao,Xing Kang,Yaxin Song,Gang Lu,Hai-Dong Yu
Organic electrochemical transistors (OECTs), particularly the ones based on PEDOT:PSS, are excellent candidates for chemical and biological sensing because of their unique advantages. Improving the sensitivity and stability of OECTs is crucially important for practical applications. Herein, the transconductance of OECT is improved by 8-fold to 14.9 mS by doping the PEDOT:PSS channel with plasmonic gold nanoparticles (AuNPs) using a solution-based process followed by photo annealing. In addition, the OECT also possesses high flexibility and cyclic stability. It is revealed that the doping of AuNPs increases the conductivity of PEDOT:PSS and the photo annealing improves the crystallinity of the PEDOT:PSS channel and the interaction between AuNPs and PEDOT:PSS. These changes lead to the increase in transconductance and cyclic stability. The prepared OECTs are also demonstrated to be effective in sensitive detection of glucose within a wide concentration range of 10 nM–1 mM. Our OECTs based on photo-annealed plasmonic AuNP-doped PEDOT:PSS may find great applications in chemical and biological sensing, and this strategy may be extended to prepare many other high-performance OECT-based devices.
研究领域:
材料科学
·
生物传感
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2023
·
IF 6.7
Lisha Fan,Jiyong Tang,Ling Wu,Shuowen Zhang,Fan Liu,Jianhua Yao,Lianbo Guo
Bismuth telluride, (Bi 2 Te 3 ), is of great scientific and technical importance due to its excellent thermoelectric performance near room temperature. However, deposition of Bi 2 Te 3 thin films suffers from composition deviation due to preferential loss of Te at a high-temperature deposition environment. We demonstrated a fast and efficient laser annealing method to synthesize high-quality stoichiometric Bi 2 Te 3 thin films at room temperature from Te/Bi stacking films. The production rate of Bi 2 Te 3 was around 180 times higher than conventional thermal annealing. The formation of Bi 2 Te 3 thin films was studied with respect to annealing laser energy density . Bi 2 Te 3 thin films with an Bi:Te atomic ratio of 2:3 were achieved at an annealing laser energy density of 6.6 mJ/cm 2 . The structural, chemical, and thermoelectric performance of laser-annealed films were compared with conventional thermally annealed films. The Seebeck coefficient of laser-annealed films reached −167 µV/K, which was1.3 higher than that of thermally annealed films, evidencing the superiority of the laser annealing method in producing high quality Bi 2 Te 3 stochiometric films. Rapid growth of stoichiometric Bi 2 Te 3 thin films by laser annealing holds great promise for the development of high-performance thermoelectric devices.
研究领域:
材料科学
·
物理学
✓ 已验证
产品关联
DOI
高影响因子
Energy Technology
·
2024
·
IF 3.6
Shuang Liu,Chaofeng Wang,Yi Guo,Jiajia Huang,Xiaohui Liu,Jing Zhang,Yuejin Zhu,Like Huang
In recent years, the field of perovskite solar cells (PSCs) has seen rapid development, with most high-efficiency devices incorporating dense titanium dioxide (TiO 2 ) barrier layers and mesoporous TiO 2 layers to enhance selective electron transport. However, the manufacturing process requires high-temperature sintering steps above 450 °C, leading to significant energy consumption. In addition, this requirement greatly limits the potential applications of PSCs in the field of flexible electronics. This study introduces a new method for preparing dense-layer-free mesoporous PSCs using low-temperature UVO annealing of m-TiO 2 . UVO annealing effectively removes residual organic components from m-TiO 2 precursor films, enhances the conductivity and wettability of the films, thereby reducing carrier recombination and improving the performance of PSCs. Research has shown that PSC with a 40 min UVO annealed m-TiO 2 layer exhibits a final photoelectric conversion efficiency of 17.79%, comparable to devices with traditional high-temperature annealed m-TiO 2 PSCs. In addition, after 7 days at room temperature and ambient humidity, the unpackaged device maintains a maximum conversion efficiency of 84%. These findings indicate that UVO light annealing is a feasible alternative to high-temperature annealing, providing a simpler, more cost-effective, and energy-saving method for the preparation of metal oxide electron transport layer in PSCs.
研究领域:
材料科学
·
能源技术
·
光伏器件
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS LETTERS
·
2021
·
IF 3.423
Zhiyuan Zhou,Jiamin Zhang,Xiyue Duan,Weiming Lin,Yang Yi,Wenjian Weng,Kui Cheng,Zuobing Chen
Graphene (Gr)/poly(vinylidenefluoride-co-trifluoroethylene) (P(VDF-TrFE)) composite films were annealed by the photothermal effect that produced between near-infrared laser and graphene. Raman spectra, X-ray Diffraction (XRD), Fourier-Transformed Infrared Spectroscopy (FTIR), Differential scanning calorimetry (DSC) are used to characterize the crystalline state of Gr/P(VDF-TrFE) films. Further, piezoelectric coefficient d 33 were to test polarization performance. Finally, the Bovine serum albumin (BSA) adsorption shows that annealing and polarization of Gr/P(VDF-TrFE) films are important for protein adsorption.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2020
·
IF 6.182
Dan Wang,Shuang Gao,Chuang Li,Yinglin Wang,Hancheng Zhu,Yichun Liu,Xintong Zhang
Efficient activation of donor-type dopants is important for promoting the photoelectrochemical (PEC) performance of semiconductor photoanodes. High temperature annealing, the most often-adopted method, can active the dopants, but is accompanied by serious deterioration of the conductive substrate. Hence, it still remains a challenge to develop a new method to activate the dopants in semiconductor photoanodes deposited on a substrate that is not resistant to high temperature. Herein, we report a pulse laser annealing (PLA) strategy to activate titanium dopant in hematite photoanodes at room temperature to improve the PEC performance for water splitting. A short treatment with 450 nm nanosecond yttrium aluminum garnet (YAG) laser (20 pulses, 30 mJ cm −2 per pulse) causes crystallinity improvement and surface roughening of hematite photoanodes without destroying the fluorine doped SnO 2 (FTO) conductive glass substrate, and results in a 1.85-fold increased photocurrent density (0.484 mA cm −2 , 1.23 V vs. RHE) of Ti-doped hematite photoanodes (5% doping level, Ti:Fe 2 O 3 -PLA). The charge transfer efficiency at the surface of Ti:Fe 2 O 3 -PLA was approximately two-fold higher than Ti:Fe 2 O 3 , and a 10.1-fold increased donor density (1.29 × 10 19 cm −3 ) was achieved, demonstrating the potential of PLA treatment for activating doped semiconductor photoanodes at room temperature.
研究领域:
材料科学
·
能源转换技术
✓ 已验证
DOI
高影响因子
JOURNAL OF PHYSICS D-APPLIED PHYSICS
·
2019
·Vol. 52
·期 38
·385105
·
IF 2.829
Cihai Chen,Huihuang Yang,Qian Yang,Gengxu Chen,Huipeng Chen,Tailiang Guo
Solution processed metal oxide thin-film transistors (MO-TFTs) have gained momentum in recent years and opened new horizons for their extended applications in thin-film optoelectronics. Unfortunately, the relatively high processing temperature has become the main limitation for their commercial application in flexible electronics. In this work, ultrashort femtosecond (fs) laser pulses were used for the annealing of printed InGaZnO TFT arrays with low temperature and fast processing. The high transient intensity and negligible heat-affected zone is beneficial to the effective conversion of precursor to metal-oxide lattices, which was also verified by the x-ray photoelectron spectroscopy analysis. Moreover, for the first time, based on optical engineering method, dielectric mirrors (DMs) is proposed to realize reflection of photon irradiation and protect the underlying polymer substrate. TFTs on polyethylene naphthalate (PEN) substrate with polymer insulator exhibited a mobility of 4.24 cm2 V−1 s−1, along with good mechanical stability. The mechanism of DMs for the improvement of the device performance was systematically investigated based on laser-matter interaction, optical structure and photon transport. DMs can reduce laser-induced pressure and variation of dielectric properties in PEN substrate resulting from the impact ionization due to a strong nonlinear multi-photon absorption. Our work clearly demonstrated that flexible MO-TFTs can be simply fabricated with fs-laser annealing. More importantly, this novel method is applicable for a wide range of MO and polymer substrates, by solving the incompatibility of solution processed MO and polymer substrates due to high processing temperature. Therefore, the proposed method showed tremendous potential to be applicable in flexible electronics such as sensors, display and circuits.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
高影响因子
THIN SOLID FILMS
·
2024
·
IF 2
Silin Han,Chongyang Li,Yuhang Chen,Yunwen Wu,Ming Li,Tao Hang
In this paper, the changes in microstructure and conductivity of the films before and after thermal and laser annealing are observed, which corresponds to various combinations of crystallite sizes and impurity densities. The results show that the impurities promote grain boundary migration at larger initial crystallite sizes, which contradicts previous reports. This is because the rate of grain growth is determined by the driving force and resistance to grain growth, the former provided by the energy of grain boundaries and the impurities outside the nanograin boundaries, and the latter by the impurities enriched within the boundaries. Additionally, laser annealing is more effective than thermal annealing in stimulating impurity diffusion, resulting in a reduced influence of impurities on grain growth.
研究领域:
材料科学
·
冶金学
·
薄膜技术
·
固体物理
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）