Search

Li metal has been regarded as one of the most promising anodes for high-energy-density storage systems due to its high theoretical capacity and lowest electrochemical potential. Unfortunately, an unstable and non-uniform solid electrolyte interphase (SEI) deriving from the spontaneous reaction between Li metal anode and electrolyte causes uneven Li deposition, resulting in the growth of Li dendrites and low Coulombic efficiency, which have greatly hindered the practical application of Li metal batteries. Thus, the construction of a stable SEI is an effective approach to suppress the growth of Li dendrites and enhance the electrochemical performances of Li metal anode. In this review, we firstly introduce the formation process of inferior SEI of Li metal anode and the corresponding challenges caused by the unstable SEI. Next, recent progresses to modify SEI layer through the regulation of electrolyte compositions and ex-situ protective coating are summarized. Finally, the remained issues, challenges, and perspectives are also proposed on the basis of current research status and progress.

In the present study, the H2S photolysis using the self-made high-frequency discharge electrodeless lamp (light distribution was 90% at 254 nm and 10% at 185 nm) was studied and simulated by MATLAB...

Although digestive resistance of Kunitz protease inhibitors has been reported extensively, the molecular mechanism is not well established. In the present study, the first X-ray structure of Cassia obtusifolia trypsin inhibitor (COTI), a member of Kunitz protease inhibitors, was solved at a resolution of 1.9 Å. The structure adopted a classic β-trefoil fold with the inhibitory loop protruding from the hydrophobic core. The role of Phe139, a unique residue in Kunitz protease inhibitors, and Arg63 in the COTI structure was verified by F139A and R63E mutants. COTI was a specific inhibitor of bovine trypsin and the result was also verified by COTI-trypsin complex formation. Meanwhile, COTI showed equivalent inhibitory activity with that of soybean trypsin inhibitor against bovine trypsin and midgut trypsin from Pieris rapae. The F139 and R63E mutants further indicated that inhibitory specificity and efficiency of COTI were closely related to the global framework, the conformation and the amino acid composition of reactive loop. Finally, a midgut trypsin from P. rapae (PrSP40), which might be involve in the food digestion, was proposed to be a potential target of COTI and might be a promising target for future crop-protection strategy. The results supported the digestive resistance of COTI.

Inspired by the photosensitivity and self-heal properties of iron oxychloride (FeOCl), we used photocatalysis coupling peroxymonosulfate (PMS) activation for effective aquatic decontamination in a cost-efficient and environmentally friendly method. Synthesized FeOCl was appointed to activate PMS to degrade bisphenol A (BPA, 2,2-bis(4-hydroxydiphenyl) propane) persistently under visible light. The best performance of FeOCl/PMS/Vis system was ∼100% BPA degradation efficiency which achieved in 20 min. The BPA removal efficiency had a positive correlation with the dosages of FeOCl and PMS, but negatively related to BPA concentration. The FeOCl/PMS/Vis system also presented impressive degradation performance at a wide pH range (pH = 3–11) and showed well excellent stability and reusability. The addition of either bicarbonate or chloride had impressive promotion effect on BPA removal. The reaction mechanism of FeOCl/PMS/Vis system was studied deeply. PMS was activated to generate active radicals (SO4 − and HO ) by Fe(II) of FeOCl for BPA degradation. Then the as-formed Fe(III) was reduced to Fe(II) via trapping photoexcited electrons in conduction band (CB) of FeOCl, which effectively inhibited the recombination of photo-generate charges and the pollutants oxidation would recur via facilitating the Fe(II)/Fe(III) redox recycle. Thus, the activation and utilization efficiency of PMS was effectively improved. This work indicated the FeOCl/PMS/Vis system was a promising application in wastewater treatment.

Desalination is one of the most effective strategies to solve the problem of freshwater shortage, which is one of the most critical challenges facing global development. Recently, the desalination battery has become an emerging desalination technology thanks to its high salt-removal capacity enabled by the high capacity of battery electrodes and low energy consumption mainly rooted from the high energy recovery during the discharge process. To promote the development of the desalination battery, we must understand the recent advances and the remaining issues in the field. Herein, we comprehensively review the development of the concept and the electrode materials for a desalination battery, summarize the performance of a full desalination battery, and propose perspectives and guidelines.

The deep interdependence between electrical and natural gas system has great influence on the security of multi-carrier energy (MCE) systems. The large-scale access to distribution generation (DG) of clean energy makes it necessary to investigate the effects of uncertainties on the safe and stable operation of MCE systems. However, the existing probabilistic energy flow analysis for MCE systems pays little attention to the difference between the correlation of various DG during calculating the energy flow. Therefore, this paper investigates the probabilistic energy flow considering the uncertainties and correlations of various DG. A framework of MCE systems considering various coupling units including power to gas (P2G) and energy hub is initially proposed. For this, the Monte Carlo simulation (MCS) method based on Latin hypercube sampling (LHS) and Nataf transformation is specially designed to calculate the energy flow for each sample. The energy flow calculation method is composed of three-phase AC/DC alternating iteration method and improved Newton node mesh method considering the control mode of compressors. Finally, the test system containing improved IEEE123-node system and NGS48-node system have verified the accuracy of the proposed probabilistic energy flow calculation method.

Photon UV irradiation is promising for organic pollutant decomposition, such as disinfection by-products (DBPs). However, due to the photostability and high water solubility, chloroacetic acids (CAAs) decomposition using routine UV photolysis is very slow. The present study employed a high photon flux UV (3.13 × 104 μmol m−2 s−1) system to investigate its feasibility and suitability for enhancing CAAs (MCAA, DCAA and TCAA) decomposition. The results showed that increasing UV photon flux accelerated the photolysis remarkably. Under the condition of high UV photon flux 3.13 × 104 μmol m−2 s−1, almost complete degradation of 20 mg L−1 MCAA, 20 mg L−1 DCAA, and 20 mg L−1 TCAA in a mixed solution can be achieved within 50, 30 and 25 min, respectively. To the best of our knowledge, efficient photolytic degradation of CAAs in such short time has not been reported. The pseudo-first-order rate constant (kobs) steadily increases with the increasing of UV intensity, indicating that the utilization of light energy is efficient. In addition, the variation of pH from 3.2 to 9.0 showed minor effect on CAAs decomposition in this present studied system. The outcome of this study would be helpful for future employment of high photon flux UV systems for those photolytic resistant pollutants' decomposition.

A power law relation between the filtration coefficients of straining and flux through small pores has been reported. The effluent concentrations of the colloidal particles and the exponents derived from the experiment are inconsistent with those obtained from 2D network models simulation in their researches. In this study, a straining-dominant deep bed filtration (DBF) model is proposed based on 3D network simulation. The effects of simulation parameters such as lattice type, lattice coordination number z , pore size distribution (PSD), and particle capture scheme on DBF were investigated. Consistent with the power law formula and the normalized effluent concentrations ( C e/ C 0 ), simulation results indicate that the exponents increase with increasing coordination number z. The change in the PSD parameters alters the flux and weight of path type linked to node, thereby influencing the numerical simulation of staining-dominate DBF on 3D networks. The effects of capture scheme and coordination number on the simulated normalized effluent concentration could be due to variations in the total capture probability for different lattices with the same PSD. The results were obtained from simulation on hexagonal close packing (HCP) and 2D triangular lattices under the optimal conditions. The simulated C e/ C 0 and exponents of the HCP lattice are similar to those of 2D triangular lattice and consistent with the experimental data.

FeOCl and Fe2O3 Fenton-like catalysts have received much attention due to low cost and high catalytic activity. However, their potential application is significantly hindered by the sluggish reduction kinetics of Fe3+ to active Fe2+. Herein, we report a novel composite catalyst FeOCl/Fe2O3/CNTs with significantly improved catalytic performance. As a result, FeOCl/Fe2O3/CNTs can degrade 100% of MB (50 mg L−1) within 20 min at low dosage of H2O2 (0.6 mM) and the superior performance is almost independent of pH in the range of 3–9. In practical application, the assembled FeOCl/Fe2O3/CNTs membrane effectively degrades continuous MB flow. This study demonstrates that incorporating electron-rich materials such as CNTs is an effective way to enhance the performance of catalysts for heterogeneous Fenton-like reaction.

Hydroxyl radicals (·OH) electrogenerated at anode surface can efficiently eliminate organic pollutants. However, these radicals are rapidly consumed and its action occurs only in the region where it is produced, thus only a portion of ·OH that are generated can be utilized and the degradation efficiency will eventually drop upon extended electrolysis. This paper proposed an alternative electro-oxidation process to avoid the mass transfer limitation and ·OH loss. This approach consists of two parts: (i) in situ electrogeneration of persulfate and (ii) subsequent UV activation. Efficient electro-generation of persulfate and degradation of phenol were obtained simultaneously when the anolyte contains sulfate ion and potassium sulfocyanide. Compared with ·OH mediated oxidation, persulfate mediated oxidation process has a small negative effect initially on the degradation rate of phenol, but then the persulfate effect became positive gradually. Phenol could be rapid eliminated once UV irradiation was added to activate the co-produced persulfate. A two-step mediated oxidation method was employed to further reduce consumed energy and sulfate dosage. Results show that the two-step method could completely eliminate the phenol in the wastewater which volume was ten times as much as that of the anolyte. An analysis of the whole reaction schemes governing this process was also presented. In summary, the persulfate mediated anodic oxidation process can be considered as a suitable and attractive method for maximizing the utilization of the electrochemical technology.

Simultaneous electrosynthesis of H 2 O 2 and persulfate was performed in a paired electrolysis system separated by a cationic membrane. To maximize the current efficiency, H 2 O 2 reacted in-situ with the added ferrous ion to form Fenton's reagent, while persulfate was used for commercial production. In the processing of electrolytic procedure, sulfate ion consumed constantly became the limiting factor for producing persulfate, while H 2 SO 4 and KSCN did not. Cyclic voltammetry test and radical quenching experiments were carried out to validate the electrosynthetic route of persulfate. During the electro-Fenton process, H 2 O 2 was decomposed into hydroxyl radical by either the added ferric ion or electron transfer reaction which resulted in a rapid degradation of phenol. The area ratio of anthode surface to anode surface was optimized to be 10:1. During the coupling process, various catholyte conditions had negligible effect on anodic electro-generation of persulfate. However, in the anode compartment the pattern was different. Hydrogen ion (H 2 SO 4 ) both in the anolyte and in the catholyte had an extensively negative effect on cathodic electrosynthesis of H 2 O 2 . Eventually, optimum conditions for the cathodic indirect oxidation of organic pollutant paired to anodic persulfate production were optimized. The coupling process can be considered as an alternative and efficient method for maximizing the utilization of the electrochemical technology.

Bisphenol A (BPA) is a kind of environmental endocrine disrupting substance, which has been used as an organic chemical as unsaturated polyester resin. The degradation of BPA includes biological methods, physical adsorption and chemical oxidation, all which have their own disadvantages. Owing to its strong oxidization capability and stable treatment performance, Fenton process can degrade organic substances at a high reactive rate and stably effective. In this paper, Fenton oxidation method was optimized to remove BPA in water, during which the intermediate products were analysed to examine its degradation path. The optimal conditions of degradation of BPA by Fenton method were a ratio of C (H2O2)/C (Fe2+) of 10, a pH of 3.5, and the degradation rate increased with the increasing of reaction temperature. It was found that Fenton could break the chemical bond at the junction of BPA and isopropyl group to produce p-diphenol, phenol, isopropyl phenol and other intermediate products.

FeOCl Fenton-like catalyst has drawn much attention due to its high catalytic activity. Nevertheless, the potential application of FeOCl is significantly hindered by the sluggish reduction kinetics of Fe3+ to active Fe2+. Here, we report that the incorporation of Fe − O–Mo electron mediator into FeOCl via forming a FeOCl/MoS2 composite can facilitate the Fe2+ regeneration through the oxidation of Mo4+ to Mo6+, which boosts the hydroxyl radicals yields, thus leading to a significantly improved catalytic performance. The removal efficiency of methylene blue (MB, 50 mg L−1) achieves ∼100% within 2 min. with low dosage of FeOCl/MoS2 (0.2 g L−1) and H2O2 (0.6 mM). FeOCl/MoS2 not only has broad working pH range (∼3 − 9) and high salinity tolerance (100 mM), but also capable to degrade various organic pollutants. For practical application, the fabricated FeOCl/MoS2 membrane effectively degrades continuous MB flow. This study demonstrates that incorporating an electron mediator is an effective way to improve the catalytic performance of heterogeneous Fenton-like catalysts.

Frequent monitoring and relatively high fines are usually necessary to bring about improvements in environmental quality, but more challenging for many countries with limited human, material, and financial resources is to put them into practice. This paper developed a three-group model of a state-dependent enforcement in a repeated game to improve the policy implementation under limited inspection capacities. A certain number of firms are grouped (group 1, group 2, group 3) for different supervision intensity (e.g., the order of inspection probability corresponding to each group is p 1