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In the contemporary context of power network protection, acknowledging uncertainties in safeguarding recent power networks integrated with distributed generation (DG) is imperative to uphold the dependability, security, and efficiency of the grid amid the escalating integration of renewable energy sources and evolving operational conditions. This study delves into the optimization of relay settings within distribution networks, presenting a novel approach aimed at augmenting coordination while accounting for the dynamic presence of DG resources and the uncertainties inherent in their generation outputs and load consumption-factors previously overlooked in existing research. Departing from conventional methodologies, the study proposes a dual-setting characteristic for directional overcurrent relays (DOCRs). Initially, a meticulous modeling of a power network featuring distributed generation is undertaken, integrating Weibull probability functions for each resource to capture their probabilistic behavior. Subsequently, the second stage employs the fuzzy Monte Carlo method to address generation and consumption uncertainties. The optimization conundrum is addressed using the ant lion optimizer (ALO) algorithm in the MATLAB environment. This thorough analysis was conducted on IEEE 14-bus and IEEE 30-bus power distribution systems, showcasing a notable reduction in the total DOCR operating time compared to conventional characteristics. The proposed characteristic not only achieves resilient coordination across a spectrum of uncertainties in both distributed generation outputs and load consumption, but also strengthens the resilience of distribution networks overall.
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In recent years, solid electrolytes (SEs) have been developed a lot due to the superior safety of solid-state batteries (SSBs) upon liquid electrolyte-based commercial batteries. Among them, garnet-type Li7La3Zr2O12 (LLZO) is one of the few SEs that is stable to lithium anode with high Li+ conductivity and the feasibility of preparation under ambient air, which makes it a promising candidate for fabricating SSBs. However, high sintering temperature (>1200 °C) prevents its large-scale production, further hindering its application. In this work, the Li5AlO4 sintering aid is proposed to decrease the sintering temperature and modify the grain boundaries of LLZO ceramics. Li5AlO4 generates in situ Li2O atmosphere and molten Li-Al-O compounds at relatively low temperatures to facilitate the gas-liquid-solid material transportation among raw LLZO grains, which decreases the densification temperature over 150 °C and strengthens the grain boundaries against lithium dendrites. As an example, Ta-doped LLZO ceramics without excessive Li sintered with 2 wt % Li5AlO4 at 1050 °C delivered high relative density > 94%, an ionic conductivity of 6.7 × 10-4 S cm-1, and an excellent critical current density (CCD) of 1.5 mA cm-2 at room temperature. In comparison, Ta-doped LLZO with 15% excessive Li sintered at 1200 °C delivered low relative density < 89%, a low ionic conductivity of â¼2 × 10-4 S cm-1, and a poor CCD of 0.5 mA cm-2. Li symmetric cells and Li-LFP full cells fabricated with Li5AlO4-assised ceramics were stably cycled at 0.2 mA cm-2 over 2000 h and at 0.8C over 100 cycles, respectively.
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Sacrificial cathode additives have emerged as a tempting strategy to compensate the initial capacity loss (ICL) in Li-ion batteries (LIBs) manufacturing. However, the utilization of sacrificial cathode additives inevitably brings residuals, side reactions, and negative impacts in which relevant researches are still in the early stage. In this study, we conduct a systematic investigation on the effects of employing a nickel-based sacrificial additive, Li2Cu0.1Ni0.9O2 (LCNO), and propose a feasible strategy to achieve advantageous surface reconstruction on LCNO. Specifically, we build a Li5AlO4 (LAO) coating layer on the LCNO through dry ball milling and annealing treatment. This process not only consumes surface residual lithium compounds on LCNO but also demonstrates minimal detrimental effects on its performance. The surface reconstructed LCNO (SR-LCNO) reveals mitigated gas generation and suppressed structure degradation under high working voltage (ï¼4.1 V), thereby causing negligible negative effects on the cycling capability and rate performance of commercial cathode materials. The full cells containing SR-LCNO deliver significantly improved electrochemical properties, with no observed exacerbation of side reactions. This work awakes the awareness of the prudent utilization of sacrificial cathode additives and provides an effective strategy for harmless pre-lithiation via surface reconstructed sacrificial cathode additives.
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Aluminized explosive has attracted more and more attention in recent years because of its high explosive heat and high power. Al2O and AlO are indispensable aluminum oxides in the explosion process of aluminized explosives. The study of the physical properties of solid Al2O and AlO under pressure may play an important role in the understanding of the explosion mechanism of aluminized explosives. CONTEXT: The structures, cold-pressed lines and electronic properties of cubic Al2O and AlO are calculated and analyzed based on first-principles calculation in this paper. The optimized structures of Al2O and AlO are in good agreement with those previously studied. The cold pressure line shows that the specific volumes of Al2O and AlO decrease with increasing pressure. The peak values and peak positions of density of state of Al2O and AlO change greatly under pressure. METHODS: The CASTEP code was used to execute these calculations throughout the present work, where the plane-wave basis set and norm conserving pseudopotential were employed.
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Phosphors composed of Gd1-xRExAlO3 (0≤x ≤ 5 RE = Dy or Pr) stoichiometries were synthesized using the reverse coprecipitation pathway. The thermoluminescent responses of all phosphors were studied under beta radiation exposure. Doping the gadolinium aluminate host improved the thermoluminescent response of the phosphors, with the phosphors composed of Gd0.99Dy0.01AlO3 and Gd0.95Pr0.05AlO3 being the most sensitive. The Dy3+ ions produced a higher improvement of the thermoluminescent signal than the Pr3+ ions. Additionally, a proportional relationship between the similarity of the atomic numbers of the dopant and replaced ions and the sensitivity to thermoluminescence was confirmed. Besides, a slight shift of the thermoluminescent peaks toward lower temperatures was detected for doped phosphors. In the repeatability tests applied to the phosphor composed of Gd0.99Dy0.01AlO3, an anomalous increase in sensitization was observed. The observed sensitization was associated with the formation of electron trap clusters resulting from the continuous exposure to beta radiation. Furthermore, another sensitization phenomenon was detected in the phosphor with Gd0.95Pr0.05AlO3 stoichiometry when it was heated at low temperatures. The aforementioned striking behavior was related to quasi-continuous distributions of electron traps and the tunneling effect. In regard to linearity, the phosphor composed of Gd0.99Dy0.01AlO3 exhibited a linear response with the dose across the entire range of beta doses. However, the response of the Gd0.95Pr0.05AlO3 phosphor lost linearity beyond 26.4 Gy of beta dose. The results obtained through the use of the Tmax-Tstop method and deconvolutions suggested an enhancement in the efficiency of the thermoluminescent mechanisms due to the incorporation of activators.
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Osteoarthritis (OA) is the most common arthritis and the leading cause of lower extremity disability in older adults. Understanding OA progression is important in the development of patient-specific therapeutic techniques at the early stage of OA rather than at the end stage. Histopathology scoring systems are usually used to evaluate OA progress and the mechanisms involved in the development of OA. This study aims to classify the histopathological images of cartilage specimens automatically, using artificial intelligence algorithms. Hematoxylin and eosin (HE)- and safranin O and fast green (SafO)-stained images of human cartilage specimens were divided into early, mild, moderate, and severe OA. Five pre-trained convolutional networks (DarkNet-19, MobileNet, ResNet-101, NasNet) were utilized to extract the twenty features from the last fully connected layers for both scenarios of SafO and HE. Principal component analysis (PCA) and ant lion optimization (ALO) were utilized to obtain the best-weighted features. The support vector machine classifier was trained and tested based on the selected descriptors to achieve the highest accuracies of 98.04% and 97.03% in HE and SafO, respectively. Using the ALO algorithm, the F1 scores were 0.97, 0.991, 1, and 1 for the HE images and 1, 0.991, 0.97, and 1 for the SafO images for the early, mild, moderate, and severe classes, respectively. This algorithm may be a useful tool for researchers to evaluate the histopathological images of OA without the need for experts in histopathology scoring systems or the need to train new experts. Incorporating automated deep features could help to improve the characterization and understanding of OA progression and development.
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The challenges associated with autonomous information processing and storage will be resolved by neuromorphic computing, which takes inspiration from neural networks in the human brain. To create suitable artificial synaptic devices for artificial intelligence, it is essential to look for approaches to improve device performance. In the present study, we suggest a method to address this problem by inserting an ultrathin AlOXlayer at the side of ferroelectric film for the prepared ferroelectric organic effect transistor (Fe-OFET) to modify a ferroelectric polymer film with a low coercive field. The transistors parameters are greatly improved (large memory window exceeding 14 V, high on-off current ratio of 103, and hole mobility up to 10-2cm2V-1s-1). Furthermore, the optimized high-performance Fe-OFET with 2 nm thickness of AlOXlayer is found to have synaptic behaviors including postsynaptic current, short-term/long-term plasticity, spike-amplitude-dependent plasticity, spike-duration-dependent plasticity, paired-pulse facilitation, spike-rate-dependent plasticity, and spike-number-dependent plasticity. An outstanding learning accuracy of 87.5% is demonstrated by an imitated artificial neural network made up of Fe-OFET for a big image version of handwritten digits (28 × 28 pixel) from the Modified National Institute of Standards and Technology dataset. By improving synaptic transistor performance in this way, a new generation of neuromorphic computing systems is set to be developed.
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This paper proposed an offset measured least regression based ALO to solve ORPD and ELD problems of IEEE 57 bus system designed with different transmission line models. These two problems are highly non-linear and non-convex defiance optimization of problem. The solution of ALO depends on exploration and exploitation if the difference between local and global variables is large, therefore chance to miss the best optimal solution. The weighted elitism phase of the algorithm gives diversified results because exploration is more biased toward elite particles. Which is due to decreasing of random walk to achieve the convergence characteristics. The proposed LSR-EALO can balance both exploration and exploitation, which improves the solution of optimization problem. Simulation is performed with proposed method on different IEEE 57 bus power system models, such as the positive sequence, 3-Phase PI, and distributed CP transmission lines based power systems, and lumped PI lines based low voltage hardware model (LVHM). In this paper, the ORPD problem was used to describe control variables like generator voltage, tap changers of transformers, and switching of capacitor banks subjected to power loss minimization function. Also, described voltage deviation and voltage stability index. Similarly, the ELD was described the active power allocation among generators to meet the sum of load demand and losses in the systems at minimum fuel cost function. And in depth analysis of the optimization results shows accuracy of control variables in ORPD and ELD problems. Also, the effectiveness of proposed method was also verified by comparing results with other meta heuristic algorithms.
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To strengthen the downscaling potential of top-gate amorphous oxide semiconductor (AOS) thin-film transistors (TFTs), the ultra-thin gate insulator (GI) was comparatively implemented using the atomic-layer-deposited (ALD) AlOxand HfOx. Both kinds of high-kGIs exhibit good insulating properties even with the physical thickness thinning to 4 nm. Compared to the amorphous indium-gallium-zinc oxide (a-IGZO) TFTs with 4 nm AlOxGI, the 4 nm HfOxenables a larger GI capacitance, while the HfOx-gated TFT suffers higher gate leakage current and poorer subthreshold slope, respectively originating from the inherently small band offset and the highly defective interface between a-IGZO and HfOx. Such imperfect a-IGZO/HfOxinterface further causes noticeable positive bias stress instability. Both ALD AlOxand HfOxwere found to react with the underneath a-IGZO channel to generate the interface defects, such as metal interstitials and oxygen vacancies, while the ALD process of HfOxgives rise to a more severe reduction of a-IGZO. Moreover, when such a defective interface is covered by the top gate, it cannot be readily restored using the conventional oxidizing post-treatments and thus desires the reduction-resistant pre-treatments of AOSs.
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Ferroelectric field effect transistor (FeFET) memories with hafnium zirconium oxide (HZO) ferroelectric gate dielectric and ultrathin InOxchannel exhibit promising applicability in monolithic three-dimensional (M3D) integrated chips. However, the inferior stability of the devices severely limits their applications. In this work, we studied the effect of single cycle of atomic-layer-deposited Al-O bonds repeatedly embedded into an ultrathin InOxchannel (â¼2.8 nm) on the Hf0.45Zr0.55OxFeFET memory performance. Compared to the pure InOxchannel, three cycles of Al-O bonds modified InOxchannel (IAO-3) generates a much larger memory window (i.e. drain current ratio between the programmed and erased devices) under the same program conditions (+5.5 V/500 ns), especially after post-annealing at 325 °C for 180 s in O2(1238 versus 317). Meanwhile, the annealed IAO-3 FeFET memory also shows quite stable data retention up to 104s, and much more robust program/erase stabilities till 105cycles. This is because the modification of strong Al-O bonds stabilizes the oxygen vacancies and reduces the bulk trap density in the channel. Furthermore, it is indicated that the program and erase efficiencies increase gradually with reducing the channel length of the memory device. By demonstrating markedly improved performance of the HZO FeFET memory with the ultrathin IAO-3 channel, this work provides a promising device for M3D integratable logic and memory convergent systems.
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Ultrasonic curing is an effective way to enhance the curing extent of composite material bonding in the aerospace industry. The non-thermal effect of ultrasonic has been revealed to improve curing efficiency. However, the mechanism of the ultrasonic non-thermal effect is still not clear. In this work, a variable activation energy model of ultrasonic curing was established by utilizing the iso-conversional method, including the activation energy of the thermal effect and activation energy of the non-thermal effect. The thermal effect caused by ultrasonic was accurately peeled off. An obvious decrease in activation energy was found from 54 kJ/mol in thermal curing to 38 kJ/mol in ultrasonic curing. The activation energy of the reaction system in ultrasonic curing was substituted into the modified Kamal autocatalytic equation, and the parameters of the ultrasonic curing kinetic model were estimated by means of an ALO algorithm. Further discussion based on in situ FTIR showed that the non-thermal effect of ultrasonic can affect the vibration strength, stability, and chemical bond energy of internal groups, but cannot cause the fracture of chemical bonds. Moreover, frontier molecular orbital analysis showed that the chemical reactivity of epoxy/amine molecules increased and the HOMO-LUMO energy gap decreased from 6.511 eV to 5.617 eV under the effect of ultrasonic.
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The preparation of highly active supported noble metal catalysts with a low noble metal loading has always been the ultimate goal of researchers working on catalysis. Hydrothermally treated Pt/Al2O3 (Pt/Al2O3-H) exhibits better catalytic activity than that (Pt/Al2O3-C) treated via the conventional calcination approach. At the high space velocity of 100,000 mL/(gâhr), the temperature that correspond to 50% toluene conversion (T50) of Pt/Al2O3-H is 115°C lower than that of Pt/Al2O3-C, and the turnover frequency (TOF) value can reach 0.0756 sec-1. The mechanism by which the hydrothermal approach enhances Pt/Al2O3 activity has been investigated. The structure associated with the high catalytic activity of Pt nanoparticles (NPs) can be retained via hydrothermal treatment. Furthermore, the support is transformed to AlO(OH) with numerous surface hydroxyl groups, which in turn can facilitate the adsorption of toluene. And the synergistic effects of Pt NPs and AlO(OH) increases the contents of Pt in oxidation state and active oxygen, which are beneficial for toluene oxidation.
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Tolueno , Adsorción , Catálisis , Oxidación-Reducción , Tolueno/químicaRESUMEN
Aqueous Al-ion battery (AAIB) is regarded as a promising candidate for large-scale energy storage systems due to its high capacity, high safety, and low cost, with MnO2 proved to be a high-performance cathode. However, the potential commercial application of this type of battery is plagued by the frequent structural collapse of MnO2 . Herein, an in situ, electrochemically reformed, urchin-like Alx MnO2 cathode is developed for water-in-salt electrolyte-based AAIBs. Benefiting from its unique α-MnO2 coated Mn2 AlO4 structure, a high Al ion storage capacity is achieved together with a high discharge voltage plateau of 1.9 V by reversible MnO2 electrolysis. Consequently, the battery exhibits a high specific capacity of 285 mAh g-1 and a high energy density of 370 Wh kg-1 at a high current density of 500 mA g-1 . Improved stability with record capacity retention is also obtained at an ultrahigh current density of 5 A g-1 after 500 cycles. Such a high-capacity and high-stability Alx MnO2 cathode would pave the way for in situ electrochemical transformation of cathode design and thus boost the practical application of AAIBs.
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Exploring new solid-state electrolyte (SSE) materials with good electrochemical stability and high Li-ion conductivity for all-solid-state Li-ion batteries is vital for the development of technologies. Herein, we employ two lithium aluminates, α- and ß-Li5AlO4 (α- and ß-LAO), as the model framework, which have an orthorhombic crystal structure and isolated AlO4 tetrahedron units connected in lithium atoms, exhibiting large band gaps, low migration barriers (0.30-0.40 eV), fast Li-ion conductivity (LIC, in a magnitude of 10-4 S/cm), and a good electrochemical stability window (ESW, [0.01-3.20 V] vs Li+/Li). We tabulate the expected decomposition products at the interface, while considering cathodes in combination with the LAO electrolyte to discuss their compatibility. We also examine the electrochemical stability, H2O/CO2 stability, and Li-ion mobility of Li4.6Al0.6Si0.4O4 (LASO), Li5GaO4 (LGaO), and Li4.6Ga0.6Ge0.4O4 (LGaGeO) compounds. In general, there is usually a trade-off between the LIC and the ESW; however, LAO features a good balance between an outstanding LIC and a wide ESW, making the compound a promising candidate for next-generation SSE materials.
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Cancer is the second leading cause of mortality worldwide, behind heart diseases, accounting for 10 million deaths each year. This study focusses on adenocarcinoma, which is a target of a number of anticancer therapies presently being tested in medical and pharmaceutical studies. The innovative study for a therapeutic vaccine comprises the investigation of gold nanoparticles and their influence on the immune response for the annihilation of cancer cells. The model is intended to be realized using Quantitative-Structure Activity Relationship (QSAR) methods, explicitly artificial neural networks combined with fuzzy rules, to enhance automated properties of neural nets with human perception characteristics. Image processing techniques such as morphological transformations and watershed segmentation are used to extract and calculate certain molecular characteristics from hyperspectral images. The quantification of single-cell properties is one of the key resolutions, representing the treatment efficiency in therapy of colon and rectum cancerous conditions. This was accomplished by using manually counted cells as a reference point for comparing segmentation results. The early findings acquired are conclusive for further study; thus, the extracted features will be used in the feature optimization process first, followed by neural network building of the required model.
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This research presents an approach for C-O grain boundary strengthening of Al composites that used an in situ method to synthesize a C-O shell on Al powder particles in a vertical tube furnace. The C-O reinforced Al matrix composites (C-O/Al composites) were fabricated by a new powder metallurgy (PM) method associated with the hot pressing technique. The data indicates that Al4C3 was distributed within the Al matrix and an O-Al solution was distributed in the grain boundaries in the strengthened structure. The formation mechanism of this structure was explained by a combination of TEM observations and molecular dynamic simulation results. The yield strength and ultimate tensile strength of the C-O/Al composites, modified by 3 wt.% polyvinyl butyral, reached 232.2 MPa and 304.82 MPa, respectively; compared to the yield strength and ultimate tensile strength of the pure aluminum processed under the same conditions, there was an increase of 124% and 99.3%, respectively. These results indicate the excellent properties of the C-O/Al-strengthened structure. In addition, the strengthening mechanism was explained by the Hall-Petch strengthening, dislocation strengthening, and solid solution strengthening mechanisms, which represented contributions of nearly 44.9%, 15.9%, and 16.6% to the total increased strength, respectively. The remaining increment was attributed to the coupled strengthening of the C and O, which contributed 20.6% to the total increase.
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In this study, AlO(OH) (boehmite) film was deposited onto a surface acoustic wave (SAW) resonator using a combined sol-gel and spin-coating technology, and prepared and used as a sensitive layer for a high-performance ammonia sensor. The prepared AlO(OH) film has a mesoporous structure and a good affinity to NH3 (ammonia gas) molecules, and thus can selectively adsorb and react with NH3. When exposed to ammonia gases, the SAW sensor shows an initial positive response of the frequency shift, and then a slight decrease of the frequency responses. The sensing mechanism of the NH3 sensor is based on the competition between mass-loading and elastic-loading effects. The sensor operated at room temperature shows a positive response of 1540 Hz to 10 ppm NH3, with excellent sensitivity, selectivity and stability.
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Kesterite Cu2ZnSn(S,Se)4 (CZTSSe) thin film is a promising material for optoelectronic devices. In this work, we fabricate Mo/CZTSSe/CdS/ZnO/ITO (ITO, indium tin oxide) heterojunction photodetectors with favorable self-powered characteristics. The photodetector exhibits exceptional high-frequency photoresponse performance whose -3 dB bandwidth and rise/decay time have reached 1 MHz and 240/340 ns, respectively. For further improvement, ultrathin Al2O3 layer prepared via atomic layer deposition (ALD) process is introduced at the Mo/CZTSSe interface. The influence of ALD-Al2O3 layer thickness and its role on the photoresponse performance are investigated in detail. The interfacial layer proved to serve as a protective layer preventing selenization of Mo electrode, resulting in the reduction of MoSe2 transition layer and the decrease of series resistance of the device. Accordingly, the -3 dB bandwidth is remarkably extended to 3.5 MHz while the rise/decay time is dramatically improved to 60/77 ns with 16 cycles of ALD-Al2O3 layer, which is 4-5 orders of magnitude faster than the other reported CZTSSe photodetectors. Simultaneously, it is revealed that the ALD-Al2O3 interfacial layer acts as an electron blocking layer which leads to the effective suppression of carrier recombination at the rear surface. Consequently, the responsivity and detectivity are enhanced in the entire range while the maximum values are up to 0.39 AW-1 and 2.04 × 1011 Jones with 8 cycles of ALD-Al2O3, respectively. Finally, the CZTSSe photodetector is successfully integrated into a visible light communication system and obtains a satisfying transfer rate of 2 Mbps. These results indicate the satisfying performance of CZTSSe-based thin film photodetectors with great potential applications for communication.
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Rechargeable lithium-oxygen (Li-O2) batteries (LOBs) with extremely high theoretical energy density have been regarded as a promising next-generation energy storage technology. However, the limited cycle life, undesirable corrosion, and safety hazards are seriously limiting the practical application of the lithium metal anode in LOBs. Here, we demonstrate a rational design of the Li-Al alloy (LiAlx) anode that successfully achieves ultralong cycling life of LOBs with stable Li cycling. Through in situ high-current pretreatment technology, Al atoms accumulates, and a stable Al2O3-containing solid electrolyte interphase protective film formed on the LiAlx anode surface to suppress side reactions and O2 crossover. The cycling life of LOB with the protected LiAlx anode increases to 667 cycles under a fixed capacity of 1000 mA h g-1, as compared to 17 cycles without pretreatment. We believe that this in situ high-current pretreatment strategy presents a new vision to protect the lithium-containing alloy anodes, such as Li-Al, Li-Mg, Li-Sn, and Li-In alloys for stable and safe lithium metal batteries (Li-O2 and Li-S batteries).
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Herein, γ-AlO(OH) as an inorganic was successfully inserted into MgAl-LDH layer by a one-pot synthesis, the composite as an adsorbent for removing methyl orange (MO) from wastewater. The structure and adsorption performance of γ-AlO(OH)/MgAl-LDH were characterized. The research shows that the expansion (003) plane and the hydroxyl active site of γ-AlO(OH)/MgAl-LDH can promote adsorption capacity and adsorption kinetics, respectively. Therefore, γ-AlO(OH)/MgAl-LDH exhibits a super adsorption performance, which completely adsorbs MO at the concentration of 1000 mg g-1. In addition, the maximum adsorption capacity of MO was 4681.40 mg g-1 according to the Langmuir model. These results indicate that γ-AlO(OH)/MgAl-LDH is a potential adsorbent for the removal of organic dyes in water.