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Aqueous zinc‐ion batteries have been identified as a viable option for grid energy storage. However, their practical application is limited by the poor performances at a high use rate of zinc. A suitable strategy to improve the cycling stability at a high depth of discharge (DOD) is by realizing the (002)‐textured Zn plating to suppress dendrite growth and side reactions. Herein, a novel electrolyte additive sodium 3‐mercapto‐1‐propanesulfonate (MPS) is introduced to regulate the zinc/electrolyte interfacial structure. The MPS anions can form an adsorption layer on the anode surface, which induces Zn deposition in the (002) direction as indicated by first‐principles calculations. Additionally, the adsorption layer can facilitate the reduction of the energy barrier associated with zinc deposition. This modified interface effectively inhibits dendrite and side reactions, resulting in a remarkable cycling lifespan for Zn||Zn symmetric cells, exceeding 800 h at a high DOD of 50%, and over 4500 h at 1.0 mA cm−2/1.0 mAh cm−2. Moreover, the capacity stability of the full cells with V2O5·H2O or polyaniline cathodes is substantially improved. A pouch‐type Zn||V2O5·H2O full cell reveals a high capacity of 42 mAh and good capacity retention of 86.6% after 250 cycles, highlighting significant potential for practical applications. [ABSTRACT FROM AUTHOR]

Zn‐N‐C possesses the intrinsic inertia for Fenton‐like reaction and can retain robust durability in harsh circumstance, but it is often neglected in oxygen reduction reaction (ORR) because of its poor catalytic activity. Zn is of fully filled 3d104s2 configuration and is prone to evaporation, making it difficult to regulate the electronic and geometric structure of Zn center. Here, guided by theoretical calculations, five‐fold coordinated single‐atom Zn sites with four in‐plane N ligands is constructed and one axial O ligand (Zn‐N4‐O) by ionic liquid‐assisted molten salt template method. Additional axial O not only triggers a geometry transformation from the planar structure of Zn‐N4 to the non‐planar structure of Zn‐N4‐O, but also induces the electron transfer from Zn center to neighboring atoms and lower the d‐band center of Zn atom, which weakens the adsorption strength of *OH and decreases the energy barrier of rate determining step of ORR. Consequently, the Zn‐N4‐O sites exhibit improved ORR activity and excellent methanol tolerance with long‐term durability. The Zn‐air battery assembled by Zn‐N4‐O presents a maximum power density of 182 mW cm−2 and can operate continuously for over 160 h. This work provides new insights into the design of Zn‐based single atom catalysts through axial coordination engineering. [ABSTRACT FROM AUTHOR]

The sulfur redox kinetics critically matters to superior lithium–sulfur (Li–S) batteries, for which single atom catalysts (SACs) take effect on promoting Li2S redox process and mitigating the shuttle behavior of lithium polysulfide (LiPs). However, conventional trial‐and‐error strategy significantly slows down the development of SACs in Li–S batteries. Here, the Li2S oxidation processes over MN4@G catalysts are fully explored and energy barrier of Li2S decomposition (Eb) is identified to correlate strongly with three parameters of energy difference between initial and final states of Li2S decomposition, reaction energy of Li2S oxidation and LiS bond strength. These three parameters can serve as efficient descriptors by which two excellent SACs of MoN4@G and WN4@G are screened which give rise to Eb values of 0.58 and 0.55 eV, respectively, outperforming other analogues in adsorbing LiPs and accelerating the redox kinetics of Li2S. This method can be extended to a wider range of SACs by coupling MN4 moiety with heterostructures and heteroatoms beyond N where WN4@G/TiS2 heterointerface is predicted to exhibit enhanced catalytic performance for Li2S decomposition with Eb of 0.40 eV. This work will help accelerate the process of designing a wider range of efficient catalysts in Li–S batteries and even beyond, e.g. alkali‐ion‐Chalcogen batteries. [ABSTRACT FROM AUTHOR]

This work focused on the evaluation of co-combustion of sewage sludge (SS) and rice husk (RH) using thermogravimetric–Fourier transform infrared spectrometry method (TG–FTIR). The thermal behavior was assessed through the combustion characteristic, interaction, kinetics, and gaseous product characteristics. The (co-)combustion process was divided into three stages. Index D exponentially increased as RH blending ratio increased and index S also increased from 10 to 70% RH blending ratio, indicating that the combustion behavior was improved by the RH blending. The activation energy was evaluated by two model-free iso-conversional methods: Flynn–Wall–Ozawa (FWO) and Kissinger–Akahira–Sunose (KAS). The minimum value of average activation energy among blends was obtained at sample with 30% RH blending, which was 103.31 kJ/mol by FWO and 97.81 kJ/mol by KAS. Several typical gaseous products and functional groups were detected by FTIR spectrum. The results showed that CO2 was the main volatile and its yield increased with the RH blending ratio. [ABSTRACT FROM AUTHOR]

• First study on application of ANN model to co-pyrolysis of SS and PS. • The predicted data of ANN were in good agreement with the experimental results. • The gas products of co-pyrolysis were detected. • Activation energy was estimated from the KAS and FWO methods. • ANN21 is the best model for predicting SS and PS pyrolysis. The co-pyrolysis characteristics of sewage sludge (SS) and peanut shell (PS) under nitrogen atmosphere were studied by thermogravimetric – Fourier transform infrared spectrometry (TG-FTIR) and artificial neural network (ANN). The proportion of PS in the experimental samples is 0, 10, 20, 30, 40, 50, 60, 70, 80, 90 and 100%. The experiments were performed at three heating rates of 5 °C/min, 7 °C/min and 10 °C/min. The variation of sample mass with temperature and gas emission were detected in this paper. SS and PS in the co-pyrolysis experiment have a synergistic effect in terms of mass loss at 335 °C ∼ 500 °C. Gases generated by pyrolysis of the mixture of SS and PS include H 2 O, CH 4 , CO 2 , CO, phenol and NH 3. The functional groups detected in the experiment include C O and C O. Apparent activation energy E was obtained by two non-isothermal kinetic analysis methods (Flynn–Wall–Ozawa and Kissinger–Akahira–Sunose). The artificial neural network method was used to predict the relationship between the mass loss of pyrolysis experiments and the change of temperature. The best ANN model (ANN21) for predicting SS and PS pyrolysis was identified. [ABSTRACT FROM AUTHOR]

• The application of C 3 N monolayer as anode for LIBs is realized by doping and strain. • Li adsorption on C 3 N monolayer is enhanced through B, O and S doping. • The Li storage capacity on C 3 N monolayer (534.42 mAh g−1) is given via O N doping. • Applied strain can further enhance Li adsorption and decrease migration barrier. Two-dimensional (2D) materials have been proved to be very promising anode materials of many kinds of batteries, including lithium-ion batteries (LIBs). The graphene-like carbon-nitrides with lightweight nature have received intense attention. The polyaniline (C 3 N) multilayer has shown its capabilities in LIBs, but C 3 N monolayer delays its arrival at application owing to too weak lithium (Li) adsorption. In this study, for the first time, the application of C 3 N monolayer as anode material for LIBs is realized by introducing heteroatom doping (B, O and S) based on first-principles simulations. The O-doped C 3 N (O N -C 3 N) offers Li storage capacity of 534.42 mAh g−1, low open circuit voltage (OCV) of 0.02 V, low Li adsorption energy of −3.64 eV and single Li atom migration energy barrier of 0.78 eV. Moreover, S N -C 3 N can dramatically lower the migration barrier of Li (0.12 eV) with respect to that on pristine C 3 N (0.41 eV). Further calculations show that the Li adsorption on C 3 N can be enhanced and migration barrier will decrease through the application of strain. This work demonstrates that heteroatom doping coupled with strain modulation is proved to be an effective and feasible strategy for the design of high-performance carbon-based 2D anode materials of batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] • Boron-containing metal-free catalysts (BC 4 N and BC 6 N 2) as efficient cathode materials of lithium-sulfur batteries. • BC 4 N and BC 6 N 2 possess stronger trapping capability for LiPs/S 8 than previously reported metal-free catalysts and perform even better than some metal-containing catalysts. • BC 4 N exhibits superior catalytic performance for Li 2 S decomposition with low energy barrier (0.8 eV) • Crystalline phase BC 4 N and BC 6 N 2 containing high density and homogeneous distribution of active boron sites could overcome the challenges faced by other carbon-based metal-free catalysts obtained via doping strategy. Lithium-sulfur (Li-S) batteries are considered as ideal next-generation energy storage devices, the commercial applications of them are hindered by their inherent drawbacks of shuttle effect and sluggish conversion among lithium polysulfides (LiPs). To tackle these issues, significant research efforts have been devoted to designing high-performance metal-based catalysts implemented in the sulfur cathodes, which however face the challenges of source scarcity and cycling instability. Here, based on first-principles calculations, we investigated our previously predicted two-dimensional (2D) metal-free boron-containing catalysts of BC 4 N and BC 6 N 2 and found that they possess strong trapping capability for LiPs adsorption energy as low as −6.41 eV beneficial for suppressing shuttle effect. Moreover, BC 4 N exhibits even superior catalytic performances toward the redox of sulfur, which can be evidenced by the low free energy change of the rate determining step of reduction reaction and small energy barrier of 0.80 eV for Li 2 S decomposition, outperforming most previously reported metal-based catalysts. Our research can pave a new way for designing new 2D metal-free catalysts in Li-S batteries, which highlights the importance of boron atoms in suppressing shuttle effect and catalyzing sulfur redox. [ABSTRACT FROM AUTHOR]