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Solar energy-powered adsorption-based atmospheric water harvesting (ABAWH) is an emerging technology for freshwater production, especially in water-scarce regions that are remote and landlocked. Numerous water adsorbents have been used in ABAWH devices to convert molecule to liquid water. However, it is still challenging to harvest water from the air in cold winter, owing to the water adsorption of sorbents decreasing significantly at low temperature. Herein, we designed and fabricated an ABAWH device by integrating composited ionic liquids (CILs) with carbon nanotubes (CNTs) photothermal materials on the surface of cotton rod fibers. CILs extract water from the air. CNTs enable light-to-heat conversion and drive the solar evaporation process. Importantly, the cotton rods offer a backbone porous structure to maintain its internal temperature at 20 °C under solar irradiation, and thus promote the water adsorption performance of CILs at low environmental temperature. Freshwater is successfully harvested under environment temperature of 6 °C, 30% RH and solar irradiation intensity of 0.6 kW m−2. The water yield can achieve 1.49 kg per m2 per day in an outdoor environment. We believe that the ABAWH device offers a promising approach to effectively harvest water from the air at low temperature and humidity conditions.

In this paper, by using the homogeneous equilibrium method, the exact solutions of a modified Bogoyavlenskii’s breaking soliton equation are derived and the soliton solutions with arbitrary functions are constructed. Then, the basic law of interaction between the different solitons are revealed and some new local structures are addressed and discussed. The periodic solitons, parabolic solitons and folded solitons of arbitrary shape propagating with variable speed are considered. It is helpful not only to verify the numerical solution and analyze the stability of the solution, but also to understand the dynamics of the high dimensional nonlinear wave field.

Planar-type perovskite solar cells (p-PSCs) based on SnO2 have garnered further attention due to their simple and low-temperature fabrication. Improving the critical properties of the electron transport layer (ETL) is an effective way to enhance the performance of p-PSC devices. Here, a brand-new method is developed to relieve the contact recombination caused by the rough fluorine-doped tin oxide (FTO) surface and further boosts the electrical concentration of the ETL. A SnO2-ethylene diamine tetraacetic acid (EDTA) acylamide compound (SEAC) with hydrogen bond-induced adjustable cluster size is reported for the first time. The rational choice of the SEAC cluster size is the key for obtaining the smooth interfacial morphology of the ETL on the rugged FTO substrate. In addition, the energy band gap decreases with the increasing cluster size, and consequently, results in improved electrical conductivity of the SEAC. The upshifted Fermi energy level leads to higher electron concentration, which is an important physical quantity of the ETL. The PSC devices based on the optimized SEAC achieve an improved power conversion efficiency of 21.29% with negligible J-V hysteresis due to significantly enhanced electron transport and reduced contact charge recombination at the ETL/perovskite interface. In general, this paper comes up with a unique strategy to improve the quality of the SnO2-based ETL.

In this paper, a high-dimensional wave soliton equation is considered and the simple Hirota method and bilinear backlund transformation are applied to construct the new soliton solutions, lump soliton solutions, breather solutions and their combined solutions. Then, through long-wave limit method and appropriate parameter constraints, one-soliton, one-breather, combined soliton-lump and lump-breather and soliton-breather solutions to nonlinear wave equation are obtained. Moreover, the physical interaction and frontal collision phenomena to the solutions of this equation are explored. In addition, a kind of hyperbolic and trigonometric ansatz is employed to derive other solutions such as kink soliton solution, periodic solutions for the high-dimensional wave equation.The obtained results verify the proposed solutions.

An inorganic caesium cation was incorporated into perovskite to improve the performance and stability of solar cells with a hole-transport-material free structure in ambient air. A triple cation device with a champion power conversion efficiency of over 15% was achieved, exhibiting superior thermal, long-term and operational stabilities.

Using a bilinear transformation and the variable separation approach, The abundant localized structures for the (2+1)-dimensional NLS equation of PT-symmetric media are explored. And Some special soliton solutions such as periodic soliton solution, dromion solutions, ring, peak, breathers and instantons type of solitons are presented by selecting the different functions appropriately. and then, the combined spatial soliton and breather solutions of the (2+1)-dimensional coupled inhomogeneous PT- symmetric nonlinear media with variable coefficients are also obtained, The propagation dynamics of combined solitons are investigated analytically and numerically, and the simulation results show they are applicable for certain potential applications in nonlinear optics and plasma physics.

Metallic Li, with ultrahigh theoretical capacity (3860 mA h g−1) and the lowest electrochemical potential (−3.04 V vs. the standard hydrogen electrode), is perfectly meet the needs of high energy density lithium batteries. However, the direct use of metallic lithium as anode would cause serious dendrite and huge volume expansion, which will bring safety hazards and restrict the practical commercialization of Li metal anodes. Herein, a facile electrophoretic deposition (EPD) method was employed for the first time to fabricate uniform TiN modified commercial Cu foam (TiN@Cu foam) as the lithiophilic 3D conductive skeleton. The lithiophilic TiN acts as the well-distributed seeds to promote the uniform lithium deposition, attributing to the lowed nucleation overpotential. The porous and conductive Cu foams can further mitigate the formation of Li dendrites, on account of its high specific surface area reduce the effective current density. The TiN@Cu foam based half cells and symmetric cells both exhibit improved reversibility and reduced polarization voltage in lithium plating/stripping process. Furthermore, better rate performance and cycling stability were also achieved in the full-cell configurations of TiN@Cu foam-Li/Li4Ti5O12 (LTO) and TiN@Cu foam-Li/LiFePO4 (LFP). This work demonstrates a facile strategy to modify the commercial current collectors with pre-synthesized lithiophilic nanoparticles for achieving uniform Li deposition.

An optimized two-step sequential deposition method to fabricate hole-transport-layer-free carbon-based methyl ammonium lead bromide (MAPbBr3) perovskite solar cells is reported. Small amounts of MABr are introduced into the PbBr2 precursor solution during the first step to prepare MAPbBr3 perovskite films (labeled as MAPB-xMABr), which promotes the conversion of PbBr2 into perovskite phase and results in denser perovskite films with increased crystallinity, lower trap density, and longer carrier lifetime. After optimization, a maximum power conversion efficiency (PCE) of 7.64% (VOC = 1.36 V) is obtained for MAPB-0.2MABr based solar cells. Significantly, the non-encapsulated devices exhibit excellent long-term stability in ambient air (25–30 °C and 20–30% relative humidity), showing no degradation after a year’s exposure. While, it also shows superior thermal stability with PCE retaining 95% of the initial efficiency after 120 h under thermal stress of 80 °C and 40–70% relative humidity.

Two dimensional materials have promising benefits in photoelectronic devices, including facilitating charge transport and reducing defects in perovskite solar cells (PSCs) and photodetectors (PDs) through interface engineering. Herein, a two dimension polymeric material of graphitic carbon nitride quantum dots (g-CNQDs) interlayer is used to modify the SnO2/perovskite interface in both ambient PSCs and PDs to improve the overall performance. The introduction of g-CNQD layer improves the crystalline quality of sequential perovskite absorber with high phase purity, less grain boundaries, low trap states and suppressed carrier recombination due to the intrinsic cross-linkable feature and relatively smooth surface of g-CNQD. As a result, with optimal modification, fully air-processed PSC reached a champion power conversion efficiency of 21.23% with negligible hysteresis, and the PDs had remarkable performance enhancement. Moreover, our PSCs have good stability in ambient air, keeping over 90% of the initial efficiency after 30 days’ exposure.

Stable hosts containing pre-stored metallic lithium (Li) are typically used to tackle irregular dendrite formation and infinite relative volume changes of lithium metal anodes. In this sense, oversimplified molten Li infusion strategies have been widely proposed to build lithiophilic architectures with uncontrollable amount and configuration of metallic Li in obtained hosts. In this work, tin oxide (SnO2) deposited Ni foam (SNF) with superior molten Li wettability is employed to construct two distinct lithiophilic architectures namely, Li coated SNF skeletons and Li infiltrated SNF frameworks. The cycling stability and dendritic behavior of these lithiophilic architectures are systematically compared. Both of these lithiophilic architectures significantly outperformed bare Li foils in terms of cycling performance and electrode dimension stability. The fully covered lithiophilic host with Li infiltrated SNF frameworks shows much better cycling stability and lower hysteresis than the porous lithiophilic host with Li coated skeletons, especially at high current densities and large stripping/plating capacities. In full-cell configurations, the batteries based on Li infiltrated SNF frameworks also show significantly higher rate capabilities than Li coated SNF skeletons counterpart. Our results provide a better understanding to design stable lithiophilic hosts for high-rate and high-capacity lithium metal anodes.

Three-dimensional branched TiO2 architectures (3D BTA) with controllable morphologies were synthesized via a facile template-free one-pot solvothermal route. The volume ratio of deionized water (DI water) and diethylene glycol in solvothermal process is key to the formation of 3D BTA assembled by nanowire-coated TiO2 dendrites, which combines the advantages of 3D hierarchical structure and 1D nanoscale building blocks. Benefiting from such unique structural features, the BTA in full bloom achieved significantly increased specific surface areas and shortened Li(+) ion/electrons diffusion pathway. The lithium-ion batteries based on BTA in full bloom exhibited remarkably enhanced reversible specific capacity and rate performance, attributing to the high contact area with the electrolyte and the short solid state diffusion pathway for Li(+) ion/electrons promoting lithium insertion and extraction.

A novel electro-hydraulic servo control algorithm was introduced. The primary idea of this algorithm was to combine the notion of model prediction with the generic model control (GMC). The performance of the GMC algorithm was improved by receding optimization and feedback correction. By the predictive model of output errors of an electro-hydraulic servo control system based on the improved weighted least square support vector machines (WLS-SVM) to forecast and compensate the future sequence errors, the control precision and robustness were improved. The improved GMC based on the improved WLS-SVM was applied to an electro-hydraulic servo control system for hot strip rolling control systems. The simulation results showed the feasibility and effectiveness of the present algorithm.

WNN(Wavelet Neural Network) is a neural networks with activation function based on wavelet. Wavelet networks are usually limited to the low-dimensional input modeling by a single network. When the input space consists of several different classes of input data, it becomes very difficult to converge the network during the training phase. In this paper, a combined wavelet-based neural network modeling was introduced to resolve this problem. Based on a gating network, a combined network can divide a complex task into subtasks, and modeling each subtask with an single WNN. The performance of such networks in modeling hot plate mill production quality is examined and compared with that of single neural network.