NANOTECHNOLOGY
·
2022
·Vol. 33
·期 35
·355701
·
IF 3.953
Guoying Yao,Liang Zhao,Tao Zeng,Zhenyu Yang
Reduced-dimensional (RD) perovskites have shown attractive chemical and physical properties for optoelectronic applications. Incorporating large organic ligands enables infinite tunability in the components and structures. Theoretically, it is feasible to apply multiple types of organic ligands in a single RD crystal to achieve multiple-dimensional perovskites. However, the coexistence of different organic ligands commonly introduces competing crystal growths that inhibit the formation of a more complex crystal structure. Herein, we report a case of mixed-dimensional (MD) perovskite single crystal containing two types of sulfide-containing ligands. We show that the application of ketones can partially oxidize organothiol ligands in the precursor solution. The resultant disulfide-based ligands can be co-incorporated with the thiol-based ligand in a single MD perovskite crystal. X-ray diffraction confirmed that the structure contains both layered and isolated inorganic components constructed by face-sharing lead halide octahedra. Unlike conventional RD structures, the MD perovskite shows an enlarged bandgap with valence band maximum and conduction band minimum being spatially separated, and isotropic optical features, as revealed by x-ray diffraction, spectroscopies, and density functional theory computation.
研究领域:
材料科学
·
化学
✓ 已验证
DOI
高影响因子
INORGANIC CHEMISTRY
·
2020
·
IF 4.825
Hang Zhang,Yujun Liang,Hang Yang,Shiqi Liu,Haoran Li,Yuming Gong,Yongjun Chen,Guogang Li
As increasing demand for noncontact temperature sensing, the development of a high-performance optical thermometer probe is more and more urgent. In this work, an efficient dual-mode optical thermometry strategy based on the Pr3+/Dy3+ energy transfer (ET) in some typical double-perovskite oxides is presented, which offers a promising way to design FIR/lifetime dual-mode optical thermometry with excellent temperature-measuring sensitivity and signal discrimination. According to this strategy, double-perovskite La2MgTiO6:Pr3+/Dy3+ phosphors are successfully synthesized. On the basis of diverse thermal responses between Pr3+ and Dy3+, the FIR of Pr3+ to Dy3+ (four FIR mode) in this material displays outstanding optical thermometry performance from 298 to 548 K. The maximum absolute and relative sensitivities (Sa and Sr) of mode 1 are 0.09 and 2.357% K–1, being better than the current optical temperature measurement materials. For the fluorescence lifetime mode, the Sa-max and Sr-max values reach 2.85 × s 10–4 and 1.814% K–1. Furthermore, the dual-mode optical thermometry mechanism was presented and studied. It also demonstrated excellent optical thermometry performance in the other Pr3+/Dy3+ codoped double-perovskite oxides, such as LaMg0.598Nb0.402O3, NaLa(MoO4)2, NaGd(MoO4)2, and NaLa(WO4)2, proving the universality of the presented strategy. This article presents an effective Pr3+/Dy3+ ET pathway for developing new and highly sensitive FIR/lifetime dual-mode optical temperature sensing materials.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
·
2021
·
IF 6.158
Yimin Liu,Jie Ma,Lili Lian,Xiyue Wang,Hao Zhang,Wenxiu Gao,Dawei Lou
An inorganic-biopolymers hybrid flocculant (PSAC-SA) was prepared by modifying sodium alginate onto polysilicate aluminum calcium (PSAC) through coordination between SA and Ca 2+ . The preparation conditions of PSAC-SA and the flocculation parameters that influence of the turbidity and color removal efficiency were investigated and optimized. The flocculation experiments results showed that the maximum turbidity and color removal could get 97.2% and 98.4% for kaolin-humic acid suspensions, respectively. The application of PSAC-SA for Songhua River treatment indicated that it had an excellent flocculation capacity in real water samples, and its flocculation efficiency was much better than that of individual flocculants (PSAC and SA). Moreover, the flocculation mechanisms were discussed in detailed, which indicated that the bridging effect and physical entrapment of solid particles played an important role in the flocculation process.
研究领域:
环境科学
·
水处理工程
✓ 已验证
DOI
高影响因子
ACTA PHYSICO-CHIMICA SINICA
·
2024
·
IF 10.8
Pengyu Dong,Yue Jiang,Zhengchi Yang,Licheng Liu,Gu Li,Xinyang Wen,Zhen Wang,Xinbo Shi,Guofu Zhou,Jun-Ming Liu,Jinwei Gao
Organic-inorganic metal halide perovskite solar cells (PSCs) are favorable candidates for next-generation solar cells, due to their excellent photovoltaic performance and promising low-cost fabrication process. Particularly, tin oxide (SnO 2 ), with excellent charge mobility and extraction efficiency, is widely used as electron transport layers (ETLs), and the efficiency of the corresponding n-i-p-type perovskites has been certified as high as 26.21% in single-junction devices. The SnO 2 layer serves as the substrate for the growth of perovskite films, determining the crystalline quality and the buried interface of perovskite films. However, due to the different thermal expansion coefficient of SnO 2 and perovskite, the subsequent perovskite annealing process leads to the residual stress at the buried interfaces and lattice distortion in the perovskite films, which seriously affects their optoelectronic performance and stability. To release this interfacial stress, researchers have made some progress by applying different polymers and small molecules to the SnO 2 /perovskite interface as a buffer layer. Among these, two-dimensional (2D) nanosheets with high carrier mobility, a wide bandgap range, and excellent optical absorption properties are promising, especially 2D NbSe 2 nanosheets showing the advantages of solution-processability, high intrinsic conductivity and clean smooth surface, namely without dangling bonded atoms. Herein, 2D NbSe 2 nanosheets have been introduced at the SnO 2 /perovskite interface to release the undesired residual tensile strain in perovskite films and to form a more matched interfacial energy level alignment. As a result, we have obtained a high-quality perovskite film and further an improved photovoltaic performance. The PCE has been increased from 21.81% to 24.05%. The unencapsulated cell maintained 91% of the initial efficiency after aging over 1000 h under atmospheric condition.
研究领域:
材料科学
·
能源技术
·
光伏器件
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF POLYMER SCIENCE
·
2024
·
IF 4.1
Zhang Xin-Rao,Wang Fu-Shan,Wang Xin,Gao Yan,Zhang Hong-Xing,Liu Zhi-Qin,Feng Jia-Chun
Although Ziegler-Natta (Z-N) polyolefins have been widely used as raw materials to produce pharmaceutical or food packaging, the migration of acid scavengers, an additive usually introduced in Z-N polyolefins, from the packaging to its contents has not been reported. In this work, the migration of the two most used acid scavengers, calcium stearate (CaSt 2 ) and zinc stearate (ZnSt 2 ), from a Z-N polypropylene random copolymer (PPR) into water during autoclaving at 121 °C were comparatively investigated. It was found that, for PPR plates containing 0.1 wt% CaSt 2 or ZnSt 2 (PPR-0.1CaSt 2 , PPR-0.1ZnSt 2 , respectively), the concentration of migrated calcium ion into water increased with autoclaving time, while that of zinc ion was much lower at same treatment durations and did not show a significant increase with treatment time. Interestingly, after removing all plates and acidification treatment, a considerable amount of stearic acid was detected in sterilized water for PPR-0.1ZnSt 2 , but no such significant stearic acid was detected in sterilized water for PPR-0.1CaSt 2 . Based on the structural evolution of the two soaps upon heating, possible mechanisms for the different migration behavior of CaSt 2 and ZnSt 2 from PPR into water during autoclaving treatment were proposed. Our results suggest that the migration issue of acid scavengers is worthy of attention in pharmaceutical packaging materials produced from Z-N polyolefins.
研究领域:
材料科学
·
食品科学
·
药学
✓ 已验证
DOI
高影响因子
Advanced Energy and Sustainability Research
·
2021
·Vol. 2
·期 6
·2000099
·
IF 0
Shoulong Chen,Xiaolin Liu,Zhen Wang,Wenhui Li,Xiaoyu Gu,Jia Lin,Tieying Yang,Xingyu Gao,Aung Ko Ko Kyaw
CsPbBr 3 -based perovskite solar cells possess both high humidity and temperature tolerance, and also have excellent long-term stability in air, but the defect states in the bulk perovskite are always an obstacle for further improvement of their efficiency. Herein, a doping strategy is demonstrated in which AgBr is directly added to the precursor solution in the first step. An appropriate amount of Ag + ion doping can passivate the defects in bulk or at grain boundaries, reduce the defect density of the film, and form a pinhole-free film. Finally, the best power conversion efficiency of the solar cell reaches to 6.92% and exhibits a long-term stability in a humid environment. This work provides a simple and effective method for improving the quality of CsPbBr 3 film and the performance of CsPbBr 3 -based perovskite solar cells.
研究领域:
材料科学
·
能源技术
·
光电子学
✓ 已验证
DOI
JOURNAL OF HAZARDOUS MATERIALS
·
2021
·
IF 10.588
Detian Dou,Donglai Wei,Xin Guan,Zhenjiang Liang,Lihong Lan,Xiongdiao Lan,Pengru Liu,Huiqun Mo,Ping Lan
Most natural polymers exhibit limited functional groups, which is not favourable for the adsorption of various ions and their utilisation. To overcome this drawback, a novel in-situ-doped nano-calcium carbonate (CaCO 3 ) chitin hydrogel was synthesised as an efficient adsorbent for Cu (II) and Cd (II) ions. Scanning electron microscopy and Brunauer–Emmett–Teller results revealed that the synthesised CaCO 3 /chitin hydrogel exhibited loose macropores and mesopores . Subsequently, Fourier transform infrared, Raman, and X-ray diffraction characterisation characterisation proved that chitin was successfully doped with nano-CaCO 3 . The mechanical properties of CaCO 3 /chitin hydrogel were superior to those of the unmodified chitin hydrogel and could efficiently adsorb Cu (II) and Cd (II) ions in water. The effect of pH, initial concentration, adsorbent dosage, and temperature was assessed to determine the adsorption properties of the hydrogel. Under suitable experimental conditions, the maximum adsorption rate of the CaCO 3 /chitin hydrogel was approximately 96%. The time-dependent adsorption kinetics followed a quasi-second order model, and the adsorption process followed the Langmuir model. The maximum adsorption capacities of Cu (II) and Cd (II) according to the Langmuir curve were 194.61 and 191.58 mg/g, respectively. Compared with the binary competitive system, the material exhibited a specific selectivity to the adsorption of Cu (II). X-ray photoelectron spectroscopy (XPS) revealed that nitrogen and oxygen atoms were involved in chelation with the metal ions. The successful compounding of calcium carbonate nanoparticles provided more active adsorption sites for the gel. The novel material exhibited excellent adsorption effects on Cu (II) and Cd (II) ions when applied to a water sample. Thus, the novel material exhibits excellent potential for application. The Cu (II) and Cd (II)ion removal efficiencies after five successive adsorption cycles were higher than 90%, which indicated that the composite material exhibited excellent stability and reproducibility.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2022
·
IF 10.383
Xiang Li,Peng Zhang,Yunqiu Hua,Fucai Cui,Xue Sun,Lin Liu,Yanxiao Bi,Zhongjie Yue,Guodong Zhang,Xutang Tao
Halide perovskites are promising candidates for soft X-ray detection (<80 keV) owing to their high X-ray absorption coefficient, resistivity, and mobility lifetime product. However, the lack of large high-quality single crystals (SCs) renders it challenging to manufacture robust hard X-ray imaging systems (>100 keV) with a low detection limit and stable dark current. Herein, high-quality inch-size two-dimensional (2D) Cs3Bi2Br9 (CBB) single crystals are grown from a melt via the Bridgman method. The crystal quality is enhanced by eliminating inclusions of CsBr-rich phases and restraining the trap-state density, leading to an enhanced resistivity of 1.41 × 1012 Ω cm and a mobility lifetime product of 8.32 × 10–4 cm2 V–1. The Au/CBB/Au single-crystal device exhibits a high sensitivity of 1705 μC Gyair–1 cm–2 in all-inorganic bismuth-based perovskites and an ultralow detection limit of 0.58 nGyair s–1 in all of the bismuth-based perovskites for 120 keV hard X-ray detection. The CBB detector exhibits high work stability with an ultralow dark current drift of 2.8 × 10–10 nA cm–1 s–1 V–1 and long-term air environment reliability under a high electric field of 10 000 V cm–1 owing to the ultrahigh ionic activation energy of the 2D structure. The proposed robust imaging system based on CBB SC is a promising tool for X-ray medical imaging and diagnostics.
研究领域:
材料科学
·
医学影像
·
辐射探测
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2021
·
IF 9.229
Wei Zheng,Ruijia Sun,Yeqi Liu,Xiaojia Wang,Nianqiao Liu,Yanchen Ji,Liangling Wang,Hong Liu,Yuhai Zhang
Despite their low toxicity and phase stability, lead-free double perovskite nanocrystals, Cs2AgInCl6 in specific, have suffered from low quantum yield of photoluminescence. This is mainly due to two reasons, including (i) the quenching effect from metal silver which was usually formed at high temperature from Ag+ reduction in the presence of organic amines and (ii) the parity-forbidden transition of pristine double perovskites. Here, we reported a room-temperature synthesis of Cs2AgInCl6 nanocrystals in an inverse microemulsion system, where Ag+ reduction was largely suppressed. By codoping Bi and Na ions, dark self-trapping excitons (STEs) were converted into bright ones, enabling a bright phosphor of photoluminescence quantum yield up to 56%. Importantly, the doping approach at room temperature relaxed the parity-forbidden transition (1S0 → 3P2) of Bi-6s2 orbitals, revealing a fine structure of a triband excitation profile. Such spin-rule relaxation was ascribed to symmetry breaking of the doped lattice, which was evidenced by Raman spectroscopy. In a proof-of-concept experiment, the bright nanocrystals were used as a color-converting ink, which enabled a stable white light light-emitting diode to operate in various environments, even under water, for long-term service.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
JOURNAL OF PHYSICS D-APPLIED PHYSICS
·
2022
·Vol. 55
·期 41
·414002
·
IF 3.409
Wenbo Ma,Zhenlong Zhang,Miao Kang,Yuefeng Liu,Huafang Zhang,Huiping Gao,Yanli Mao
Dion–Jacobson (DJ) quasi-two-dimensional (quasi-2D) perovskite solar cells (PSCs) have attracted increasing attention owing to their potential stability compared with the Ruddlesden-Popper (RP) phase. It is known that the low efficiency and poor thermal stability retard the application of quasi-2D PSCs. Here, DJ quasi-2D perovskite films based on propane-1.3-diammonium (PDA) spacer cations were prepared by a hot casting technique. Ionic liquid additive of 1-butyl-3-methylimidazolium tetrafluoroborate (BMIMBF4) was introduced into the quasi-2D perovskite precursor solution to improve the crystal quality and morphology of the films. The quasi-2D PSCs with BMIMBF4 achieved an optimal power conversion efficiency (PCE) of 14.07%, which is higher than the 12.45% of the control devices. The impressive 1.17 V high open-circuit voltage and 14.07% efficiency are the highest values for the reported PDA-based n–i–p type devices. Moreover, the thermal stability of the solar cells was significantly enhanced by the addition of BMIMBF4. The PCE of the devices with BMIMBF4 maintains 72% of the initial value after annealing at 85 °C for 120 h, while the PCE of control devices drops to 19% of the initial value. These results prove that the introduction of ionic liquid BMIMBF4 is a pragmatic method to elevate the efficiency and thermal stability of quasi-2D PSCs.
研究领域:
材料科学
·
能源科学
·
光伏技术
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2017
·Vol. 52
·期 10
·5857-5870
·
IF 2.599
Zhao Bei,Shen Dingyi,Tan Qinyue,Tang Jianfeng,Zhou Xianju,Hu Shanshan,Yang Jun
CaF 2 :Ln 3+ (Ln = Ce, Tb, Eu) phosphors with highly uniform shapes have been successfully synthesized by a simple hydrothermal method directly. The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), photoluminescence (PL) and lifetime. The results indicated that the pH values, organic additive and reaction time have a significant effect on the morphology and dimensions of CaF 2 microcrystals and the possible formation mechanism was also proposed. Furthermore, the energy transfer from Ce 3+ to Tb 3+ and from Tb 3+ to Eu 3+ and from Ce 3+ to Tb 3+ to Eu 3+ was observed and the corresponding mechanisms were discussed in detail. The CaF 2 :Ln 3+ phosphors may have potential optical applications in near-UV and violet LEDs.
研究领域:
材料科学
·
无机化学
·
光学材料
·
纳米技术
·
固体化学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2014
·
IF 5.9
Huaqiao Tan,Zhao Zhao,Wan-bin Zhu,Eric N. Coker,Binsong Li,Min Zheng,Weixing Yu,Hongyou Fan,Zaicheng Sun
A facile and general method has been developed to fabricate oxygen vacancies on perovskite SrTiO3 (STO) nanocrystals through a controllable solid-state reaction of NaBH4 and SrTiO3 nanocrystals. STO samples with tunable color, oxygen vacancy concentration on nanocrystal surface have been synthesized. TEM results reveal that these STO samples have a crystalline core/amorphous shell structure (SrTiO3@SrTiO3–x). XPS and EPR results disclose that the oxygen vacancy concentration increases with the increase of reaction time and temperature. The concentration of oxygen vacancies calculated from TGA data, could reach 5.07% (atom) in this study. UV–vis spectra and photocatalytic results indicate that oxygen vacancies on STO surface play an important role in influencing the light absorption and photocatalytic performance. However, an excess amount of oxygen vacancies leads to a decrease of photocatalytic performance. The optimal photocatalytic activity for H2 production under UV–vis irradiation is up to 2.2 mmol h–1 g–1, which is about 2.3 times than the original SrTiO3, corresponding to 3.28% (atom) of oxygen vacancy concentration.
研究领域:
材料科学
·
光催化
·
纳米材料
·
表面化学
·
能源材料
·
无机化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）