Nanoscale
·
2019
·Vol. 11
·期 39
·18272-18281
·
IF 6.97
Shun-Xin Li,Guo-Ping Zhang,Hong Xia,Yi-Shi Xu,Chao Lv,Hong-Bo Sun
The detection of the polarization states of light is of great significance for the analysis of biological tissue morphologies, image display systems and sensors. Although organic–inorganic hybrid perovskite crystals have excellent photoelectric properties, which make them very suitable for the preparation of photodetectors, their applications in polarized light detection are hindered by their isotropy and instability. Here, we solved this problem by fabricating a stable 2D layered Ruddlesden–Popper perovskite into anisotropic micro-wire arrays with a template-confined method. Based on this anisotropic structure, a high-performance photodetector with a dark current as low as 10−12 A, high responsivity of 3.5 A W−1, detectivity exceeding 1 × 1015 Jones and a fast response with a rise time of 4.1 ms and a decay time of 3.3 ms was achieved and successfully applied for high-performance polarization detection. More importantly, the device maintained a superior performance even after being exposed to an environment of 60% relative humidity without encapsulation.
研究领域:
光电子学
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材料科学
·
钙钛矿光子学
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偏振检测
·
纳米制造
✓ 已验证
DOI
高影响因子
Cell Reports Physical Science
·
2023
·
IF 8.9
Yi Wei,Yanan Sun,Yufeng Liu,Jiawen Song,Jingwei Mao,Chunxiang Li,Jing Liu,Zijian Deng,Lujun Pan,Ze Yu,Xichuan Yang,Jijun Zhao
Two-dimensional Ruddlesden-Popper perovskites (2D-RPPs) have emerged as promising candidates for efficient solar cells. However, compositional complexity and their multiphase nature make them particularly susceptible to strain, which can have detrimental effects on their device performance and stability. Here, we focus on cyclohexane methylamine (CMA)-based 2D-RPPs and modulate the strain by substituting iodide with bromide. These mixed-halide 2D-RPPs show excellent optical properties, with mixability and tunable band gap. As the substitution ratio increases, the 2D-RPP framework undergoes a sudden rearrangement in crystal lattice, effectively releasing the strain in lattices. Benefiting from the strain relaxation, the 2D-RPPs exhibit evident improvement in crystallinity, which significantly suppresses recombination in the device and enhances carrier transport across it. Consequently, we achieve an increase of 1.15% in efficiency with the strain-released devices containing (CMA) 2 MA 8 Pb 9 I 26.4 Br 1.6 . This device shows significantly improved stability, retaining 93% of the initial efficiency after exposure to 55%–85% relative humidity (RH) for 120 days.
研究领域:
材料科学
·
能源科学
✓ 已验证
DOI
高影响因子
Materials
·
2023
·Vol. 16
·期 14
·5195
·
IF 3.4
Jun Yang,Jinbiao Pang,Xiaofang Luo,Laiyuan Ao,Qiang Xie,Xing Wang,Hongyu Yang,Xianzhong Tang
This work studied the phase constitution, bond characteristics, and microwave dielectric performances of Sr2TiO4ceramics. Based on XRD and Rietveld refinement analysis, pure tetragonal Ruddlesden–Popper type Sr2TiO4ceramic is synthesized at 1425~1525 °C. Meanwhile, the microstructure is dense and without porosity, indicating its high sinterability and densification. Great microwave dielectric performances can be obtained, namely anεrvalue of 39.41, and aQ × fvalue of 93,120 GHz, when sintered at 1475 °C. Under ideal sintering conditions, the extrinsic factors are minimized and can be ignored. Thus, the intrinsic factors are considered crucial in determining microwave dielectric performances. Based on the P–V–L complex chemical bond theory calculation, the largest bond ionicity, and proportions to the bond susceptibility from Sr–O bonds suggest that Sr–O bonds mainly determine the dielectric polarizability. However, the Ti–O bonds show lattice energy about three times larger than Sr–O bonds, emphasizing that the structural stability of Sr2TiO4ceramics is dominated by Ti–O bonds, and the Ti–O bonds are vital in determining the intrinsic dielectric loss. The thermal expansion coefficient value of the Sr2TiO4structure is also mainly decided by Ti–O bonds.Keywords:Sr2TiO4;microwave dielectric properties;P–V–L complex chemical bond theory
研究领域:
材料科学
·
物理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2023
·
IF 5.2
Zhi Yang,Jian Zhang,Bingxue Wu,Xin Zhao,Xuanlin Lu,Yicheng Zhao,Yongdan Li
The oxygen reduction reaction at the cathode is an essential process for protonic ceramic fuel cells . Composite cathode materials are commonly used towards the multiple requirements including high surface oxygen activity as well as sufficient electronic and ionic conductivities . In this study, a cobalt-free composite cathode composed of a perovskite La 0.6 Sr 0.4 FeO 3-δ phase and a Ruddlesden-Popper La 1.2 Sr 0.8 NiO 4+δ phase is synthesized with a self-assembly technology. The cathode process is mainly controlled by (I) the reduction of adsorbed oxygen atom to O − on the surface and (II) the migration of O − from the surface into the lattice. The former benefits from the high electrical conductivity of La 0.6 Sr 0.4 FeO 3-δ , and the latter is accelerated by La 1.2 Sr 0.8 NiO 4+δ attributed to its superior oxygen activity. The one-pot synthesized composite cathode shows an enhanced synergistic effect due to the uniform distribution of the two phases at the nanoscale. The cathode shows the lowest polarization resistances of 0.055 and 0.095 Ω cm 2 at 700 °C in oxygen and air, respectively. The results show that self-assembled La 0.6 Sr 0.4 FeO 3-δ -La 1.2 Sr 0.8 NiO 4+δ nanocomposite is a promising cathode material for protonic ceramic fuel cells.
研究领域:
材料科学
·
能源科学
✓ 已验证
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2026
·
IF 5.8
Zhi Zhang,Zhenyu Lei,Zhenkang Sun,Mengfei Zhang,Yu Zhang,Qi Yang,Xinru Ma,Shengnan Chen,Jia Li,Minkai Qin,Yunyi Cao,Jianguo Liu
Developing durable oxygen evolution reaction (OER) electrocatalysts is pivotal for hydrogen production but hindered by sluggish kinetics. While Ruddlesden-Popper (RP) oxides offer a versatile platform, they often suffer from limited active site density. Herein, we present a targeted B-site engineering strategy to activate bilayer RP ferrites (La 0.25 Sr 2.75 Fe 2 O 7 ) via systematic Ni incorporation. This substitution strengthens B-O covalency and enriches oxygen vacancies. The optimized LSFN50 exhibits a low overpotential of 344 mV at 10 mA cm -2 , surpassing commercial IrO 2 . Mechanistic studies indicate a pH-dependent pathway. Systematic structural and chemical analyses reveal that high-valence Ni 3+ and Fe-Ni synergy drive surface reconstruction into active oxyhydroxides, with lattice oxygen participation further boosting reaction kinetics. Significantly, an anion exchange membrane (AEM) water electrolyzer employing the LSFN50 anode delivers an industrial-grade current density of 2.23 A cm -2 at 1.9 V. This study highlights the critical role of B-site modulation in designing high-performance catalysts for practical energy conversion.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
·
2018
·
IF 6.759
Hong Zhang,Shuang Ni,Yongli Mi,Xiaoxiang Xu
Doping techniques generally serve as effective means for tailoring the physicochemical properties of a target compound. In this work, we successfully co-doped La/Fe into Ruddlesden-Popper (RP) compound Sr 2 TiO 4 and performed a detailed investigation on the crystal structure, morphology, optical absorption and photocatalytic hydrogen production reactions after doping. Our findings suggest that La/Fe co-doping slightly expand the unit cell of Sr 2 TiO 4 while maintains the structure lamination. Incorporating La/Fe into Sr 2 TiO 4 efficiently reduces the band gap and the level of band gap reduction can be controlled by varying the amounts of dopants. La/Fe co-doping significantly improves the photocatalytic properties of Sr 2 TiO 4 under both full range (λ ≥ 250 nm) and visible light illumination (λ ≥ 420 nm). A fivefold enhancement in hydrogen production rate (∼106.2 μmol/h) is seen in sample Sr 1.9 La 0.1 Ti 0.9 Fe 0.1 O 4 (x = 0.1). Efficient photocatalytic hydrogen production under visible light illumination (λ ≥ 420 nm) is also achieved in sample Sr 1.7 La 0.3 Ti 0.7 Fe 0.3 O 4 (x = 0.3) with AQE as high as ∼1.18% at 420 nm. DFT calculations confirm the critical role of Fe in reducing the band gap of Sr 2 TiO 4 by forming additional spin-polarized bands (SPB). The anisotropic charge transportation in Sr 2 TiO 4 is also verified by our calculations as both conduction band minimum (CBM) and valence band maximum (VBM) are buried in TiO 6 octahedron layers. The 2D charge transportation properties are particularly useful for photocatalytic reactions since interlayer charge recombination is essentially prevented.
研究领域:
材料科学
·
光催化
·
能源材料
·
固态化学
✓ 已验证
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2021
·
IF 8.198
Ping Li,Runze Dong,Ruochen Wang,Tianqi Shao,Fei Yan,Pan Zhang,Dong Fu,Rujie Wang
In view of high catalytic activity and oxygen vacancy concentration, Ruddlesden–Popper (R-P) structure oxide has been widely used as the electrode material for solid oxide fuel cells (SOFCs). Herein, three R-P structure oxides, Pr2–xSrxNi0.2Mn0.8O4 (x = 1, 1.2, and 1.5), are used as the semiconductor materials of single-component cells. The materials for the oxygen side are hybrid oxides consisting of R-P structure oxide and perovskite oxide. The hydrogen side was exposed to the reduction atmosphere before the test, and the perovskite structure disappeared and the lattice parameters of the R-P structure changed, resulting in the formation of a new R-P structure and MnO2 or NiMn alloy. In addition, Pr0.5Sr1.5Ni0.2Mn0.8O4 and reduced Pr0.5Sr1.5Ni0.2Mn0.8O4 exhibit the most content of oxygen vacancy. For a single-component fuel cell (SCFC), the cell performance increased with the decrease in Pr content. The SCFC composed of Pr0.5Sr1.5Ni0.2Mn0.8O4 shows the highest maximum power densities (Pmax), which reached 206.6 mW cm–2 at 700 °C. It is because the reduced Pr0.5Sr1.5Ni0.2Mn0.8O4 has the highest catalytic activity for hydrogen oxidation reaction (HOR). Furthermore, the Pmax at 700 °C can reach a value of 198.1 mW cm–2 in SOFC mode, and in the case of SOEC mode, the current density at 700 °C is as high as −390.8 mA cm–2 with an applied electrolysis voltage of 1.3 V for the reversible single-component cell (RSCC) with Pr0.5Sr1.5Ni0.2Mn0.8O4 as the semiconducting electrocatalyst.
研究领域:
材料科学
·
能源工程
·
电化学
·
燃料电池
✓ 已验证
DOI
高影响因子
DALTON TRANSACTIONS
·
2012
·Vol. 41
·期 37
·11507-11518
·
IF 3.838
Minfeng Lü,Xiaolong Deng,João C. Waerenborgh,Xiaojie Wu,Jian Meng
The n = 1 Ruddlesden–Popper (RP) phases LaSrM0.5Ru0.5O4±δ (M = Co, Ni and Zn) have been prepared by solid state reactions and structurally characterized by powder X-ray and electron diffraction. All the samples adopt the tetragonal I4/mmm space group with random M and Ru cation occupation on the B-sites. The potential causes of no cation ordering are discussed. A combined analysis of the tolerance factors, the distortion of the octahedral coordination of M and Ru cations and the magnetic interactions between M and Ru cations provide a better understanding for forming a phase with 3D cation ordering on the B-sites in the n = 1 RP phases. The investigation of XPS spectra suggests that the transition element species exist as mixed ion pairs, Ru(4−δ)+–Ru4+ ↔ Co2+–Co3+ in LaSrCo0.5Ru0.5O4, and Ru4+–Ru(4+δ)+ ↔ Ni+–Ni2+ in LaSrNi0.5Ru0.5O4, which is consistent with cation disorder over the B sites. LaSrCo0.5Ru0.5O4 shows a weakly ferromagnetic behaviour below 50 K; LaSrNi0.5Ru0.5O4 is evidenced by the presence of long-range magnetic ordering at a Néel temperature of 125 K, and LaSrZn0.5Ru0.5O4 exhibits a paramagnetic behaviour down to 5 K. Due to atomic disorder, Ru4d, O2p covalent coupling is weakened, strengthening the intraatomic spin–spin coupling among the π* electrons. Charge transfer between Ru and Co or Ru and Ni, as well as the increasing overlap of both nearest-neighbour and next-nearest-neighbour Ru 4d electrons due to atomic disorder, favour the formation of ferromagnetic interactions. Although antiferromagnetism is dominant, particularly in LaSrNi0.5Ru0.5O4, ferromagnetic interactions are stronger in the title compounds than in the related La2MRuO6 (M = Co, Ni) double perovskites where the B-site cations are ordered.
✓ 已验证
DOI
高影响因子
Materials Science and Engineering B-Advanced Functional Solid-State Materials
·
2026
·
IF 5.7
Yingyun Li,Ruizhu Li,Na Gao,Tao Li,Jian-Qiang Wang,Guoping Xiao
Sluggish catalytic activity and long-term stability of oxygen electrode materials are the main challenges in the commercialization of solid oxide fuel cells (SOFCs). Herein, a Ruddlesden-Popper-structured Pr 2-x La x NiO 4+δ (PLxN) by A-site lanthanum doping are investigated to enhance catalytic activity and stability of oxygen electrodes. Interestingly, the PL 0.1 N electrode exhibits low polarization resistance of 0.090 Ω cm 2 at 800 °C, with 18.18% reduction compared to PNO. Furthermore, the Pr 1.9 La 0.1 NiO 4+δ in anode-supported single cells exhibit peak power density of 1.468 W cm −2 at 800 °C and good operational stability over 100 h. Thereinto, La-doping induces lattice expansion and charge redistribution, which enriches surface active sites and accelerates oxygen reduction reaction kinetics. Overall, trace La-doping serving as an A-site defect engineering provides an efficient design strategy for high performance SOFC cathodes.
✓ 已验证
DOI
高影响因子
Advanced Optical Materials
·
2025
·
IF 7.2
Yiyun Luo,Tingting Yan,Xinglong Zhang,Wushuang Han,Enliu Hong,Xiaosheng Fang
2D Ruddlesden-Popper (RP) phase perovskite single crystals feature significant optoelectronic properties owing to their unique structural characteristics. Introducing an asymmetric electrode configuration on 2D layered perovskites is expected to exhibit interesting interfacial contact phenomena and greatly enhance their optoelectronic performance. Herein, 2D RP-phase perovskite (PEA) 2 PbBr 4 (PPB) single-crystalline microplates, with thickness ranging from ≈60 to ≈350 nm, are prepared by the liquid–air interfacial method. Asymmetric contact barriers are constructed with two different metal electrodes on the perovskite microplates to improve the photodetection performance and obtain a preferable self-powered photodetection capability. The optimized asymmetric barrier and excellent band alignment facilitate efficient photogenerated charge dissociation and extraction, boosting the biased photocurrent by 5.59 × 10 4 times compared to symmetric electrode devices. Crucially, by constructing contact barriers with two different metal electrodes, a preferable self-powered (PEA) 2 PbBr 4 photodetector is achieved. The asymmetric photodetector exhibits a high on/off ratio of 7.69 × 10 3 and maintains an ultralow dark current (3.28 × 10 −13 A) with high photocurrent (2.41 × 10 −9 A) in self-powered mode. This study highlights a simple and effective strategy using asymmetric electrodes to improve the performance of a 2D RP-phase perovskite photodetector, advancing the understanding of carrier transport dynamics and material-electrode contact behavior of 2D perovskites.
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Xiaojuan Lu,Deyu Xin,Lin Lei,Zhenghui Fan,Siyin Dong,Shujie Tie,Ruihan Yuan,Pu’an Lin,Jianguo Zhu,Xiaojia Zheng
Halide perovskites have emerged as promising candidates in X-ray detection due to their strong X-ray absorption and excellent optoelectronic properties. The development of sensitive and stable flat-panel X-ray detectors with high resolution is crucial for practical applications. In this paper, we introduce a novel flat-panel X-ray detector that integrates quasi-two-dimensional (2D) Ruddlesden–Popper (RP) perovskite with a pixeled thin film transistor (TFT) backplane. We incorporate 2,5-dibromopyrimidine (DBPM) as an additive to passivate the Lewis acid defects in the quasi-2D RP perovskite. This modification results in suppressed ion migration, improved optoelectronic performance, and enhanced operational stability of the device. Impressively, the activation energy of the RP perovskite increases from 0.96 to 1.35 eV with the DBPM additive. As a result, X-ray detectors exhibit a high sensitivity of ∼13,600 μC Gyair–1 cm–2, a low detection limit of 6.56 nGyair s–1, and excellent operational stability. Moreover, the flat-panel detectors demonstrate a high spatial resolution of 3.7 line pairs per millimeter and excellent X-ray imaging properties under a remarkably low X-ray dose of ∼50 μGyair, which is just half of the X-ray dose typically used in commercial equipment. This study opens new avenues for the development of flat-panel perovskite X-ray detectors with significant potential for various applications.
研究领域:
材料科学
·
医学影像
·
电子工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2023
·
IF 9.5
Mengli Hu,Yu Zhang,Ning Meng,Wei Wang,Yao Lu,Jie Dong,Suling Zhao,Bo Qiao,Dandan Song,Zheng Xu
Quasi-two-dimensional (quasi-2D) perovskites exhibit excellent performance when applied to light-emitting diodes (LEDs). However, quasi-2D perovskite films generally have nonuniform n phases and irregular internal crystal structures, which degrade the device’s performance. Here, we propose using a Dion–Jacobson (DJ)-type organic spacer to modulate the phase distribution of the Ruddlesden–Popper (RP) quasi-2D perovskite. A DJ-type organic spacer cation, 1.6-hexamethylenediamine (HDABr2), was introduced into the perovskite as the second spacer cation with propylamine hydrobromide (PABr). As DJ-type and RP-type perovskites have similar spacings, RP–DJ style does not cause a chaotic crystalline structure; instead, it modulates the perovskite crystallization and narrows the phase distribution. In parallel, there is a substantial improvement in the maximum luminance, current efficiency, external quantum efficiency, and device stability of the quasi-2D perovskite LEDs. This work provides a novel concept for combining the organic spacer cations for quasi-2D perovskites.
研究领域:
材料科学
·
光电技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）