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The strategy of ternary blend is one of the most important approaches to enhance the power conversion efficiency (PCE) for polymer solar cells (PSCs). The present work prepared a new series of ternary PSCs, PBDB-T-2F:IT-4F:ITIC, based on the perspective of compatibility of non-fullerene molecule (ITIC) and its derivative (IT-4F) and studied the effect of the third component (ITIC) on the morphology and photoelectric conversion process of PBDB-T-2F:IT-4F solar cells. The results showed that surface roughness and phase scale of the PBDB-T-2F:IT-4F changed with the ITIC content, leading to variable morphology, optical, photophysical and electrical characteristics in ternary blend active layers. When the content of ITIC reached 20%, the ternary PSCs achieved the highest PCE (13.41%) among the PSCs. Morphology and optical spectroscopy studies showed that the enhanced performance of ternary device can be attributed to the morphology optimization of ternary active layer with the content of ITIC, and consequently the improved charge photogeneration processes. This work provided another way to achieve the high-performance ternary polymer solar cells via the combination of compatible non-fullerene molecules.

A novel amphoteric membrane was designed by blending polyvinylpyrrolidone (PVP) with sulfonated poly(ether ether ketone) (SPEEK) to fabricate a vanadium redox flow battery. Acid–base pairs were formed by sulfonic acid and heterocyclic nitrogen, and the dense network structures were interwoven by the hydrogen bonds between the acid–base pairs. Vanadium ions were blocked by these network structures such that their penetration was weakened. Compared with Nafion115 and SPEEK membranes, the ion selectivity of SPEEK/PVP (S/P) hybrid membranes of various proportions was improved, of which the S/P-30% membrane performed best (106.1*104 S min cm−3). At the same time, these hybrid membranes showed far superior performances than the single-component membranes in a single-cell system. Most notably, the coulombic efficiency and energy efficiency achieved by the battery with a S/P-30% hybrid membrane were 97.5% and 84.5% at 60 mA cm−2, respectively, with notable stability after 50 cycles. The corresponding open-circuit voltage of the battery was maintained above 0.8 V for more than 73 h. This acid–base hybrid membrane has reached a high level of overall performance in binary non-fluorine proton exchange membranes in recent years.

As the largest emitter of CO2 emissions, the installed capacity of thermal power generation in China is facing more and more strict restrictions, since the Chinese government proposed to dissolve overcapacity and intends to solve the problem of continuous reduction in utilization rate of electricity sector. Regretfully, the impact of power-generating capacity and its utilization on carbon emissions in the power sector has not yet been addressed. In this study, we incorporate the interaction between capacity and utilization of power sector into the dynamic spatial Durbin model, and estimate the specific impact on carbon dioxide emissions from the power sector based on the panel data set of China’s provinces during 1991–2015. The results show that both installed capacity and utilization rate have positive effects on CO2 emissions. Interestingly, the estimation coefficient of their interaction term is negative, implying that the carbon emission reduction effect derives from the conflicting performance of capacity governance and utilization efficiency. Besides, the advantage of the emerging econometric method, the dynamic spatial Durbin model (SDM) with provinces and time-period fixed effects, is that it can estimate spatial interaction effects among the provinces and neighboring provinces and decompose those effects into two parts: long-term and short-term. However, the estimates indicate that only capacity has roughly significant spatial spillovers. As a result, dissolving overcapacity of thermal power generation and a necessary interprovincial coordination will promote carbon emission reduction rather than investing in coal-fired power plants, and the power authority should turn to alternative investment in cleaner power generation technologies.

A facile synthetic strategy was developed for in-situ preparation of two-dimensional (2D) highly crystalline tungsten nitride (WN) nanosheets with controllable morphology as oxygen reduction reaction (ORR) catalysts. The dependence of the crystal structure and morphology of WN on K2SO4 content, pH, and pyrolysis temperature was thoroughly examined. The electrocatalytic performance of WN toward ORR in an alkaline electrolyte indicated that K+ plays an important role in the control of size and shape in the hydrothermal and nitridation process, thereby promoting the formation of plate-like WO3 and 2D WN nanosheets. The WN nanosheets, with largely exposed edge sites, provide abundant catalytic active sites and allow fast charge transfer. Furthermore, they exhibit high stability for ORR and methanol tolerance.

Due to the fact that the turbine outlet temperature of aeroderivative three-shaft gas turbine is low, the conventional combined cycle is not suitable for three-shaft gas turbines. However, the humid air turbine (HAT) cycle provides a new choice for aeroderivative gas turbine because the humidification process does not require high temperature. Existing HAT cycle plants are all based on single-shaft gas turbines due to their simple structures, therefore converting aeroderivative three-shaft gas turbine into HAT cycle still lacks sufficient research. This paper proposes a HAT cycle model on a basis of an aeroderivative three-shaft gas turbine. Detailed HAT cycle modelling of saturator, gas turbine and heat exchanger are carried out based on the modular modeling method. The models are verified by simulations on the aeroderivative three-shaft gas turbine. Simulation results show that the studied gas turbine with original size and characteristics could not reach the original turbine inlet temperature because of the introduction of water. However, the efficiency still increases by 0.16% when the HAT cycle runs at the designed power of the simple cycle. Furthermore, simulations considering turbine modifications show that the efficiency could be significantly improved. The results obtained in the paper can provide reference for design and analysis of HAT cycle based on multi-shaft gas turbine especially the aeroderivative gas turbine.

Aiming to further promote the performance of PdNi for formic acid electro-oxidation (FAEO), ternary Pd-Ni-Ir/C nanocatalyst was synthesized via an ethylene glycol-assisted NaBH4 reduction process. The physical characterizations show that the PdNiIr nanoparticles with a small mean size are well dispersed on carbon support. The electrochemical measurements demonstrate that the PdNiIr/C catalyst exhibits the highest activity for FAEO. The onset and peak potential of FAEO on PdNiIr/C is about 70 mV more negative than that on the Pd/C and PdNi/C catalysts. The mass activity of Pd in PdNiIr/C at 0.14 V is 2830 mA mg−1Pd, which is about 1.65, 1.82, and 2.2 times as high as that of PdIr/C, PdNi/C, and Pd/C, respectively. The enhancement should be attributed to the electronic effect and bi-functional mechanism.

Apple-derived porous carbon (denoted as APC) is successfully prepared and analyzed as a potential carbon material by hydrothermal carbonization and pyrolysis, which exhibits a high specific surface area and porous structure. Furthermore, nickel–cobalt double hydroxide (Ni–Co DH) is synthesized by design of hybrid nanowires on APC for supercapacitors via a simple hydrothermal process. The fabricated electrode produces a capacitance of 1519 F g−1 at 1 A g−1, and 90.2% of the capacitance is retained after 2000 cycles at a high current density. An asymmetric supercapacitor (ASC) is assembled using the Ni–Co DH@APC as the positive electrode and active carbon as the negative electrode. The ASC exhibits a prominent energy density of 61.2 Wh kg−1 and high power density of 14,400 W kg−1 at 5 A g−1. The desirable electrochemical performance can be attributed to the suitability of APC as a support and the Ni–Co nanostructure constructed on the surface of APC as an effective active material for high-energy and long-life cycling supercapacitor applications. The fabricated composite provides a potential design of low-cost functional carbon materials that can be produced in large scale by using biomass as starting materials.

Novel nanohybrid MgFe2O4 (MFO) supported on carbon black co-doped by nitrogen and sulfur (CNS) was facilely synthesized as an efficient electrocatalyst (namely, MFO/CNS) for oxygen reduction reaction (ORR) in alkaline medium. Structural analysis by X-ray diffraction revealed the formation of MFO and confirmed its spinel structure in MFO/CNS nanocomposite. Transmission electron microscope images showed that the products synthesized by different annealing temperature displayed a diverse particle size and dispersion of active component. Electrochemical results indicated that the MFO/CNS hybrid with the controllable N, S-co-doping shows an enhanced ORR catalytic activity and desired direct four-electron reaction pathway, which is better than MFO and CNS synthesized under the same conditions. The excellent electrochemical performance of MFO/CNS should be attributed to the synergistic effect of MFO and CNS to form a conductive network structure, which offers the increased electrochemical active surface area, the facilitated electron transfer, and effective mass transport between oxygen molecules and active sites. The results demonstrated that the MFO/CNS nanohybrid in this study appears to be a promising cathodic electrocatalyst in alkaline fuel cells.

Sulfonated poly(ether ether ketone)/poly(vinylidene fluoride)/graphene (S/P/G) composite membrane was prepared through a solution-casting method for a vanadium redox flow battery (VRB), and the weight ratio of high sulfonated poly(ether ether ketone) (SPEEK), polyvinylidene fluoride (PVDF), and graphene was optimized. The preferred S/P/G-7 composite membrane showed the lowest VO2+ permeability and highest ion selectivity compared with other four kinds of cation exchange membranes SPEEK75, heterogeneous PSSA-PE, Nafion 117, and recast Nafion (r-Nafion). The VRB with S/P/G-7 membrane exhibited the higher coulombic efficiency of ∼8% and energy efficiency of ∼4%, but lower capacity loss and self-discharge than that of VRB with Nafion117 membrane during cycling tests, which further indicated the promising prospects of S/P/G-7 composite membrane in VRB application.

It is well known that lithium-ion transport in olivine LiFePO4 is through one-dimensional (1D) channels along the [010] direction. Therefore, the crystal structure of LiFePO4 should be controlled to shorten Li+ diffusion pathway and orient {010} facets. In this work, LiFePO4 nanoplates with preferred growth {010} active facets are synthesized by hydrothermal method in the presence of NH4 + and ascorbic acid. The effects of organic additive on the morphologies and structures are characterized by XRD and SEM. It is recognized that organic additive plays a critical role in crystal growth in hydrothermal reaction and a rational mechanism is speculated. In addition, LiFePO4/C is prepared by mixing procedure of LiFePO4 nanoplates with 30 wt% ascorbic acid and carbonized at 600 °C for 5 h in Ar atmosphere. The resulting LiFePO4/C sample is used as cathode materials for lithium-ion batteries. The electrochemical performances are evaluated by galvanostatic charge–discharge cycling tests and cyclic voltammetry. LiFePO4/C displays a high initial discharge capacity of 163.62 mAh/g at 0.1C (1C = 170 mA/g) between 2.5 and 4.2 V.

The ferroelectric relaxor behavior and dielectric properties of La2O3 and Y2O3 co-doped (Ba0.9Ca0.1)(Zr0.2Ti0.8)O3 ceramics prepared by solid route were investigated. The phase structure, microstructures and dielectric properties of the as-prepared samples were characterized by X-ray diffraction, scanning electron microscopy and impedance analyzer respectively. The results show that La3+ ions and Y3+ ions substitute for A-sites ions and B-sites ions respectively to enter the unit cell maintaining the perovskite structure of solid solution, inducing inhomogeneous microstructure, smaller grain size and lower density, then resulting the occurrence of ferroelectric relaxor behavior. The relaxor behavior was observed in (Ba0.9Ca0.1)0.995La0.005(Zr0.2Ti0.8)O3–x mol% Y ceramics and the degree of ferroelectric relaxation behavior is enhanced with the increase of Y3+ ions concentration. The dielectric constant increases with x = 0.0–0.1 then decreases with further addition, the sample with x = 0.1 shows a giant permittivity (21,736) with lower dielectric loss (0.063) and could be an attractive material for ceramic capacitor applications.

Carbon dioxide (CO2) is the principal cause of the greenhouse effect which is due to the excessive consumption of fossil fuels. Several methods have been proposed for reducing CO2 emissions in the atmosphere but none has been completely successful. Recently, a novel technique called the CO2-mineralization cell (CMC) technique, based on CO2 mineralization and utilization (CMU), was proposed by our group. This converts chemical energy from the CO2 mineralization reaction into electricity while also producing highly valuable chemical products. However, some confusion and doubts still exist about its theoretical feasibility. Herein, a thermodynamics study and analysis of the CMC were conducted and the feasibility of generating electricity by CO2-mineralization reaction confirmed theoretically. The corresponding theoretical electromotive force and the maximum electric energy production per 1t carbon dioxide completely consumed under standard conditions were also calculated, and their influential factors fully discussed.

The Cu(In, Ga)Se2 (CIGS) thin films were deposited on bare glass and DC sputtered preferential oriented Mo-coated glass by RF sputtering from a single quaternary target. The structural and morphological properties of the films were characterized by X-ray diffraction (XRD), Raman spectroscope, energy dispersive X-ray spectrometer (EDS) and atomic force microscope (AFM). Preferred orientation of the Mo back contact was tuned between (110) and (211) plane by controlling the thickness. All the deposited CIGS thin films show (112) preferred oriented chalcopyrite structures. The films prepared on Mo-coated glass show higher quality crystallinity, better stoichiometry composition and more smooth surface morphology. Especially, the film on (211) oriented Mo-coated glass with the best integrated performance is expected to be a candidate absorber for high-efficiency CIGS solar cell device.

To obtain highly dispersed and active Pd/C catalysts for formic acid electro-oxidation (FAEO), carbon supported Pd nanoparticles were prepared by three different synthesis methods. The first Pd deposition technique went through the ethylene glycol (EG)-assisted sodium borohydride (NaBH4) reduction process (Pd/C-EG-NaBH4). The second method was the polyol process (Pd/C-EG). The third method was the general NaBfLt reduction process (Pd/C-NaBH4). The results of x-ray diffraction and transmission electron microscopy (TEM) show that the Pd particles on carbon black prepared by the first method have the smallest average size of 3.5 nm with a narrow size distribution. Cyclic voltammetry was used to characterize the electrochemical performance. The peak current density (mass activity) of the Pd/C-EG-NaBH4 for FAEO is 1742 mA/mgPd, which is 1.45 times higher than that of Pd/C-EG and 1.48 times higher than that of Pd/C-NaBH4. Moreover, the experimental results show that the first method has no dependence on the pH value of the synthesis procedure, while the other two methods in the literature are greatly affected by the pH value.

A series of phthalonitrile end-capped sulfonated polyarylene ether nitriles are synthesized via K2CO3 mediated nucleophilic aromatic substitution reaction at various molar ratios. The as-prepared polymer structures are confirmed by 1H NMR and FTIR spectroscopy. The properties of membranes cast from the corresponding polymers are investigated with respect to their structures. The membranes exhibit good thermal and mechanical properties, low methanol permeability (0.01 × 10−6–0.58 × 10−6 cm2·s−1 at 20 °C), and high proton conductivity (0.021–0.088 S·cm−1 at 20 °C). The introduction of phthalonitrile is proved to increase intermolecular interaction, mainly contributing to the reduction in water uptake, swelling ratio, and methanol permeability. More importantly, its introduction does not decrease the proton conductivity, but there is a slight increase. Furthermore, the selectivity of SPEN-CN-50 can reach 4.11 × 105 S·s·cm−3, which is about nine times higher than that of Nafion 117. All the data show that the as-prepared membranes may be potential proton exchange membrane for DMFCs applications.

After a 21-year-old woman experienced 2 weeks of fever, chills, and lymphadenopathy, extensive cotton-wool spots appeared in the posterior pole of the fundus, with massive occlusion of the retinal arterioles and capillaries. Purtscher-like retinopathy may occur after a viral infection with lymphadenopathy. The visual recovery is heavily related to vascular occlusion in the macular region.