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Coordination environment engineering is developed to synthesize Fe SA /NSC catalysts with the tailored N, S co-coordinated Fe atomic site. [Display omitted] • The Fe-N 3 S active site with the optimized electronic structure is constructed. • S doping promotes the OH* desorption, thus leading to enhanced kinetics process. • The catalyst displays impressive ORR activity in both alkaline and acidic mediums. • The catalyst exhibits excellent performance in Zn-air batteries and fuel cells. Atomically dispersed iron–nitrogen-carbon (FesbndNsbndC) materials have been considered ideal catalysts for the oxygen reduction. Unfortunately, designing and adjusting the electronic structure of single-atom Fe sites to boost the kinetics and activity still faces grand challenges. In this work, the coordination environment engineering is developed to synthesize the Fe SA /NSC catalyst with the tailored N, S co-coordinated Fe atomic site (Fe-N 3 S site). The structural characterizations and theoretical calculations demonstrate that the incorporation of sulfur can optimize the charge distribution of Fe atoms to weaken the adsorption of OH* and facilitate the desorption of OH*, thus leading to enhanced kinetics process and intrinsic activity. As a result, the S-modified Fe SA /NSC exhibits outstanding catalytic activity with the half-wave potentials (E 1/2) of 0.915 V and 0.797 V, as well as good stability, in alkaline and acidic electrolytes, respectively. Impressively, the excellent performance of Fe SA /NSC is further confirmed in Zn-air batteries (ZABs) and fuel cells, with high peak power densities (146 mW cm−2 and 0.259 W cm−2). [ABSTRACT FROM AUTHOR]

[Display omitted] Enhancing the electrocatalytic oxygen evolution reaction (OER) performance is essential to realize practical energy-saving water electrolysis and CO 2 electroreduction. Herein, we report a bimetallic co-doping engineering to design and fabricate nickel–cobalt-iron collaborative oxy-hydroxide on nickel foam that labeled as NiCoFeO x H y -NF. As expected, NiCoFeO x H y -NF exhibits an outstanding OER activity with current density of 10 mA cm−2 at 194 mV, Tafel slope of 53 mV dec−1, along with the robust long-term stability, which is significantly better than bimetallic NiCo and NiFe combinations. Comprehensive computational simulations and characterizations jointly unveil that the twisted ligand environment induced by heteroatoms ensures the balance strength between the metal–oxygen hybrid orbital states and the oxidized intermediates adsorption, thus lowering the oxygen cycling energy barriers for overcoming the sluggish OER kinetics. Moreover, a novel phase transition behavior is monitored by in-situ Raman spectra under OER operating conditions, which facilitates electron-mass transfer as well as boosts the exposure of activity sites. For practical applications, Ni 2 P-NF || NiCoFeO x H y -NF and Cu || NiCoFeO x H y -NF couples were constructed to realize high-efficiency water electrolysis and CO 2 electrochemical reduction for the production of valuable H 2 and C 2 H 4 , respectively. This work elucidates a novel mechanism by which bimetallic co-doping improves the electrocatalytic OER activity of nickel-based hydroxides. [ABSTRACT FROM AUTHOR]

Heteroatoms-modified Fe–N–C catalysts have garnered significant attention for enhancing the oxygen reduction reaction (ORR). However, revealing the correlation between the type of heteroatoms used for doping and catalytic performance still faces significant challenges. Herein, based on the density functional theory (DFT), a series of heteroatom-modified Fe–N–C models with the tailored Fe–N 4 -X (X = S, P or B) site are constructed to explore the regulatory mechanism of heteroatoms on the electronic structure and adsorption behavior of Fe centers. Theoretical calculations reveal that the doping of S atoms can optimize the electronic environment of Fe atoms, thus leading the favorable interaction between Fe–N 4 –S site and OH intermediates. As a result, the Fe–N 4 –S site possess a lower energy barrier for the desorption of OH* than that of Fe–N 4 –B and Fe–N 4 –P, indicating higher catalytic activity and kinetics of S-modified Fe–N–C catalysts. [Display omitted] • Heteroatom-modified Fe–N 4 models are analyzed by theoretical calculations. • S doping can optimize the electronic structure around Fe–N 4 sites. • S doping promotes the OH* desorption, thus leading to enhanced kinetics process. • Fe–N 4 –S model exhibits higher activity and stability than Fe–N 4 –B and Fe–N 4 –P. [ABSTRACT FROM AUTHOR]

With the scarcity of fuel energy, non-noble metal compounds assisted water of electrolysis is becoming a potential candidate for cost-effective and high-quality hydrogen production. To date, transition metal phosphide (TMP) has been considered as one of the most promising catalysts for water splitting because of its multitudinous but controlled constituent elements and stoichiometric ratios. In this review, the electronic structure analysis of TMP dialectically reveals the active derivation for catalyzing hydrogen evolution (HER) and oxygen evolution reaction (OER). And then the strategies of rationally designing the structure and composition of electrocatalyst to improve its intrinsic activity are discussed, especially interface engineering. Besides, this review also focuses on the negligible stability issue during the water splitting process. In the end, some key challenges and research orientations of TMPs are pointed out, which is instructive for developing high-efficient and stable electrocatalysts for water splitting. • The activity derivation of transition metal phosphide (TMP) for water splitting. • Optimization strategies for TMPs to modulate their electron structure. • Strategies to improve conductivity and durability for the first time. • Prospects for the development of the design and synthesis of TMP in water splitting. [ABSTRACT FROM AUTHOR]

Highlights: A promising solar-powered environmentally friendly process for the synthesis and application of catalysts for hydrogen evolution reaction has been proposed. A delicate NiCo(OH)x-CoyW catalyst with a bush-like heterostructure was realized via gas-template-assisted electrodeposition, followed by electrochemical etching process. The excellent catalytic effect of NiCo(OH)x-CoyW for the hydrogen evolution reaction was systematically investigated through various physical and electrochemical analyses.To achieve high efficiency of water electrolysis to produce hydrogen (H2), developing non-noble metal-based catalysts with considerable performance have been considered as a crucial strategy, which is correlated with both the interphase properties and multi-metal synergistic effects. Herein, as a proof of concept, a delicate NiCo(OH)x-CoyW catalyst with a bush-like heterostructure was realized via gas-template-assisted electrodeposition, followed by an electrochemical etching-growth process, which ensured a high active area and fast gas release kinetics for a superior hydrogen evolution reaction, with an overpotential of 21 and 139 mV at 10 and 500 mA cm−2, respectively. Physical and electrochemical analyses demonstrated that the synergistic effect of the NiCo(OH)x/CoyW heterogeneous interface resulted in favorable electron redistribution and faster electron transfer efficiency. The amorphous NiCo(OH)x strengthened the water dissociation step, and metal phase of CoW provided sufficient sites for moderate H immediate adsorption/H2 desorption. In addition, NiCo(OH)x-CoyW exhibited desirable urea oxidation reaction activity for matching H2 generation with a low voltage of 1.51 V at 50 mA cm−2. More importantly, the synthesis and testing of the NiCo(OH)x-CoyW catalyst in this study were all solar-powered, suggesting a promising environmentally friendly process for practical applications. [ABSTRACT FROM AUTHOR]

Searching for ideal candidates with high electrocatalytic performance for both HER and OER is a major objective to realize the large-scale H 2 production by seawater electrolysis. Herein, we report delicate, heterostructured NiTe-NiCoN and NiTe-NiFeN electrocatalysts, which exhibit outstanding HER and OER performance, respectively. Impressively, the NiTe-NiCoN || NiTe-NiFeN couples in alkaline seawater solution delivered 400 mA cm−2 at 1.84 V along with long-term stability. Further analysis has revealed that not only heterogeneous interface engineering ensures exposure of abundant active sites and faster electron-mass transfer, but also induces electron modulation that optimizes the absorption/desorption for the reaction intermediates to enhanced the intrinsic activity. Notably, a high electric field intensity generated by the nanosheet-nanorod structure induces a local "hydroxide enrichment" environment that promotes the OER kinetics. This work shed lights on these novel heterostructured electrocatalysts with strong synergy, while demonstrating the key role of the unique nanostructures in high-efficiency seawater electrolysis. [Display omitted] • NiTe-NiCoN and NiTe-NiFeN with core-shell nanorod arrays ensure a high active area, good electrical conductivity and seawater corrosion resistance. • Electronic modulation to enhance the intrinsic activity is achieved through interfacial synergy between metal nitrides and nickel telluride. • The nanostructure-induced "hot spots" effect modulates the electric field state to promote seawater OER kinetics and suppress the side effects of chlorine. [ABSTRACT FROM AUTHOR]

We demonstrate a high optoelectronic performance and application potential of our random network, with subwavelength diameter, ultralong, and high-quality silver nanowires, stabilized on a substrate with a UV binder. Our networks show very good optoelectronic properties, with the single best figure of merit of ∼1686, and excellent stability under harsh mechanical strain, as well as thermal, and chemical challenge. Our network transparency strongly exceeds the simple shading limit. We show that this transmission enhancement is due to plasmonic refraction, which in an effective medium picture involves localized plasmons, and identify the inhomogeneous broadening as the key factor in promoting this mechanism. Such networks could become a basis for a next generation of ultrahigh-performance transparent conductors. [ABSTRACT FROM AUTHOR]

[Display omitted] Copper-based tandem catalysts are effective candidates for yielding multi-carbon (C2+) products in electrochemical reduction of carbon dioxide (CO 2 RR). However, these catalysts still face a significant challenge regarding in the low selectivity for the production of a specific product. In this study, we report a high selectivity of 77.8 %±2 % at −1.0 V (vs RHE) for the production of C 2 H 4 by using a Cu 88 Ag 12 NW catalyst which is primarily prepared through a combined Cu-Ag co-deposition and wet chemical method, employing an attractive strategy focused on regulating the microenvironment over Cu-Ag nanowires. The experimental and computational studies show that the higher *CO coverage and lower intermediate adsorption energy are important reasons for achieving the high C 2 H 4 selectivity of Cu 88 Ag 12 NW catalyst. Comsol simulation results indicate that dense nanowires exhibit a nano-limiting effect on OH− ions, thereby leading to an increase in local pH and promoting coupling reactions. The catalyst demonstrates no noticeable decrease in current density or selectivity even after 12 h of continuous operation. The Cu-Ag nanowire composite exhibits remarkable catalytic activity, superior faradaic efficiency, excellent stability, and easy synthesis, which highlights its significant potential for electro-reducing carbon dioxide into valuable products. [ABSTRACT FROM AUTHOR]

Rational design and fabrication of high-efficiency electrocatalysts is essential for improving the kinetics of both oxygen evolution reaction (OER) and oxygen reduction reaction (ORR), so as to constructing high-performance rechargeable zinc-air batteries (ZABs). Among the promising candidates, transition metal-based (oxy)hydroxides have attracted extensive attention for their considerable catalytic potential on oxygen-involved reaction, while unsatisfactory intermediate adsorption/desorption strength and low conductivity limit their practical feasibility. In this work, interface engineering modification strategy is proposed, and a metal–organic framework derived heterostructure catalyst of CoFeO x H y -CoP@CC is fabricated. Comprehensively analyses demonstrate that the interaction between phosphide-(oxy)hydroxide induces the interfacial electronic redistribution, while the formed Schottky heterostructure facilitates rapid electron transfer. All these kinetically favorable for both OER and ORR, and leads to remarkable bifunctional performance on CoFeO x H y -CoP@CC, with the OER overpotential of 240 mV to deliver the current density of 10 mA·cm−2, which is better than CoP@CC, CC and RuO 2. In practical applications, liquid zinc-air cells assembled by CoFeO x H y -CoP@CC deliver the peak power density up to 117.55 mW cm−2, which is close to that of 20% Pt/C catalyst (108.48 mW cm−2), and considerable operational performance has also been achieved in all solid-state flexible ZABs. • A metal–organic framework derived phosphide-hydroxide heterostructure of CoFeO x H y -CoP@CC was fabricated. • Heterogenous interaction tunes the electronic configuration and facilitates rapid electron transfer, so that enhances electrocatalytic OER and ORR performance. • CoFeO x H y -CoP@CC employed as cathode in both liquid and solid zinc-air cells show considerable operational performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • A Zn 5 (OH) 6 (CO 3) 2 -assisted pyrolysis strategy is proposed to prepare a coupled catalyst. • Fe nanoparticles can optimize electronic structures and d-band center of Fe center. • Fe-FeN-C exhibits eminent ORR activity with a E 1/2 of 0.921 V in alkaline media. • The Zn-air batteries deliver high power density and long-cycle life for 408 h. Fe single-atom catalysts still suffer from unsatisfactory intrinsic activity and durability for oxygen reduction reaction (ORR). Herein, the coexisting Fe single atoms and nanoparticles on hierarchically porous carbon (denoted as Fe-FeN-C) are prepared via a Zn 5 (OH) 6 (CO 3) 2 -assisted pyrolysis strategy. Theoretical calculation reveals that the Fe nanoparticles can optimize the electronic structures and d-band center of Fe active center, hence reducing the reaction energy barrier for enhancing intrinsic activity. The Zn 5 (OH) 6 (CO 3) 2 self-sacrificial template not only can promote the formation of Fe single atoms, but also contributes to the construction of microporous/mesoporous/macroporous structures. Therefore, the obtained Fe-FeN-C exhibits impressive ORR activity with a half-wave potential of 0.921 V, which far exceeds Pt/C. With Fe-FeN-C as the cathode catalyst, the assembled Zn-air batteries delivered a maximum power density of 206 mW cm−2 and a long-cycle life over 400 h. [ABSTRACT FROM AUTHOR]

Sepsis is a life‐threatening disease characterized by multiple organ dysfunction. B cells play a pivotal role in sepsis. Here, we first observed the significantly reduced Flot2 gene expression in B cells from patients with bacterial sepsis and endotoxin‐induced septic mice. However, the effects of Flot2 on sepsis and B‐cell immunity remain unknown. Thus, we sorted B cells from Flot2 knockout (Flot2−/−) mice, RNA‐seq revealed significantly upregulated effector B cell (Beff) cytokines such as Il6, Il1b and Cxcl10 after Flot2 deficiency, while it showed no effect on the expression of regulatory B cell (Breg) cytokines such as Il10, Tgfb. Consistently, elevated Beff cytokine IL‐6 and unchanged Breg cytokine IL‐10 were shown in B cells from Flot2−/− mice. Similar results were subsequently observed in B cell‐specific Flot2 knockout chimeric mice. Notably, Flot2 deficiency aggravated sepsis with increased lung injury and shortened survival time in vivo by facilitating Beffs but not Bregs. Taken together, our data identify Flot2 as a novel controller of B cells, Flot2 deficiency amplifies inflammation by affecting Beffs to participate in the pathogenesis and progression of sepsis. [ABSTRACT FROM AUTHOR]

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has become a global pandemic. The interplay between innate and adaptive immune responses plays a crucial role in managing COVID-19. Cell therapy has recently emerged as a promising strategy to modulate the immune system, offering immense potential for the treatment of COVID-19 due to its customizability and regenerative capabilities. This review provides an overview of the various subsets of immune cell subsets implicated in the pathogenesis of COVID-19 and a comprehensive summary of the current status of immune cell therapy in COVID-19 treatment. [ABSTRACT FROM AUTHOR]

The electrochemical characterization of new electrode materials in the lithium battery field is commonly conducted using a simplified two-electrode configuration, known as the "half-cell" concept. However, this approach often overlooks the critical error related to the polarizability of the lithium electrode, especially when the working electrode has a high areal capacity and the half-cell undergoes long-term cycling. In our work, we propose a simple way to improve the properties of the Li electrode, which is using a superstoichiometric Li 1+x Al surface enrichment of the metallic lithium foil in situ by direct contact with aluminum foil, serving as a counter/reference electrode. The method eliminates the inhomogeneity of the lithium surface and creates a buffer zone between the highly active lithium electrode and liquid organic electrolytes. The high lithium content in the surface alloy allows the electrode to behave like a lithium electrode while providing low polarization and maintaining a stable potential throughout the long duration of cycling. By implementing this method, we improve the charge/discharge characteristics of high-capacity electrodes and obtain more accurate evaluations of their electrochemical performance. [Display omitted] • A new counter/reference electrode——Li@Li 1+x Al electrode. • The Li@Li 1+x Al electrode exhibits an equilibrium potential of Li one. • The Li@Li 1+x Al electrode is more stable than Li electrode in coin-type half-cell. [ABSTRACT FROM AUTHOR]

[Display omitted] • Suppressing effect of NBT on cobalt electrodeposition is confirmed by electrochemical analysis and in situ Raman spectra. • Accelerating effect of NBT on HER is studied by electrochemical methods and finite element simulation. • Suppressing-accelerating effect of NBT is proposed to illustrate the influence of NBT during cobalt electrodeposition. • Nitrotetrazolium blue chloride and convection is of grain refinement during cobalt electrodeposition. Achieving cobalt superconformal (bottom-up) growth is significantly important. Electrochemical methods, including cyclic voltammetry, electrochemical impedance spectra and EQCM-derived Coulomb-voltage curves, were used to confirm the suppressing influence of new suppressor Nitrotetrazolium Blue chloride (NBT). In situ Raman spectroscopy was used confirm that NBT can effectively adsorb on cobalt surface. Besides, EQCM-derived Coulomb-voltage illustrates that it is more beneficial for cobalt electrodeposition at high pH. The NBT effect on hydrogen evolution reaction (HER) was studied by LSV and chronoamperometry. Finite element simulation is used to investigate the accelerating effect of NBT on HER and convection. Suppressing-accelerating effect is proposed to illustrate effect of NBT. NBT can not only suppress the cobalt deposition but also can accelerate local convection by intensifying HER, which can in turn strengthen NBT adsorption. SEM analysis demonstrates that convection and NBT can refine grain. High-quality cobalt is achieved with low SDT values ranging from 24 μm to 45 μm and high FP values (75.4 % for 150 μm, 88.9 % for 100 μm and 87.2 % for 50 μm). [ABSTRACT FROM AUTHOR]

• Based on the constant potential implicit solvent model, a realistic electrocatalytic environment was simulated. • The ORR activity of S-coordinated FeN 4 was simulated using a constant potential implicit solvent model. • It was found that FeN 4 S2 exhibited the highest activity under -2e conditions with an overpotential of 0.39V. • The high electronegativity of S enhances the valence state of Fe, weakens adsorption of *OH, and promotes the ORR process. The widespread application of S doping in Fe-N-C materials aims to enhance the catalytic activity for oxygen reduction reactions (ORR). However, the current doping strategies are primarily centered on the first coordination layer encompassing Fe atoms. Consequently, this study employs first-principles calculations to compute the formation and binding energies of FeN 4 doped with S atom. It further delves into the influence of diverse doping sites on catalyst stability and meticulously analyzes the configurations and corresponding ORR activities of four catalysts, namely FeN 4 S-N (Number=0∼3), utilizing a constant-potential implicit solvent model to simulate authentic electrocatalytic environments. The findings reveal that under vacuum conditions, FeN 4 S1 exhibits the utmost ORR activity, boasting a potential of 0.53 V. Conversely, within the constant-potential implicit solvation model, FeN 4 S2 emerges as the catalyst with the highest ORR activity, achieving a potential of 0.39 V. Therefore, calculations leveraging the constant-potential solvation model offer more realistic insights into catalyst design, thereby guiding the development of superior catalysts. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • HP-Fe-N-C/2 exhibits eminent ORR activity and stability in alkaline and acidic media. • The Zn-air battery shows high power density and superior cyclability for 1342 h. • The power density of HP-Fe-N-C/2-based PEM fuel cell is up to 0.66 W cm−2. Atomically dispersed Fe-N-C catalysts are a promising alternative to platinum group metal (PGM) catalysts for oxygen reduction reaction (ORR). However, attaining efficient ORR activity and superior stability in Fe-N-C catalysts is still crucial yet challenging. Herein, we report a rational SiO 2 -mediated two-step pyrolysis strategy for stabilizing densely exposed Fe-N 4 active sites on hierarchically porous carbon (HP-Fe-N-C/2). Benefiting from the high density of accessible Fe-N 4 sites and the high graphitization degree of carbon support, the obtained HP-Fe-N-C/2 catalyst demonstrates outstanding activity and stability for ORR in both alkaline and acidic media. When used as the cathode catalyst, the assembled Zn-air battery shows a high peak power density of 217 mW cm−2 and ultra-long cycling stability for 1342 h without noticeable degradation. As a PGM-free cathode in proton exchange membrane fuel cells, it delivers a maximum output power density of 0.66 W cm−2. [ABSTRACT FROM AUTHOR]

[Display omitted] • A comprehensive overview of atomically dispersed M−N−C catalysts for ORR. • Focus on active site engineering to improve activity and stability in fuel cells and Zn-air batteries. • Future directions of developing advanced M−N−C catalysts for ORR are outlined. Atomically dispersed metal-nitrogen-carbon (M−N−C) oxygen reduction reaction (ORR) catalysts have been proven as one of the most promising non-precious metal catalysts. In this review, we summarize recent advances in the active site engineering toward M−N−C catalysts for ORR, which focuses on modulating coordination environment of active sites to enhance intrinsic activity, such as coordination structures, heteroatomic doping M−N−C, dual-atom sites, coupled catalytic sites, and defective M−N−C. Moreover, the strategies for increasing the density and utilization of active sites are discussed, including chelation, stepwise atom doping, spatial confinement, surface exposed M−N x sites, and porous structure optimization. Thereafter, the performance decline mechanisms are introduced and the strategies for improving stability are systematically analyzed by regulating the structure of the active center and carbon support. Finally, we also proposed the future perspectives of M−N−C catalysts. This review aims to provide some guidelines towards synthesis of M−N−C catalysts for fuel cells and Zn-air batteries. [ABSTRACT FROM AUTHOR]

The methanesulfonate system is gradually replacing the traditional highly polluting fluoride electroplating lead （Pb） system with its eco-friendly advantage, and searching for suitable additives is crucially important to obtain uniform Pb coatings in the methanesulfonate system. In this work, a potential additive of thiourea suitable for methanesulfonate-based Pb electroplating was screened based on the theoretical calculations and cyclic voltammetry tests, and the effect of thiourea in the Pb electrodeposition was investigated. Specifically, the adsorption-coordination mechanism was proposed to explain the effect of thiourea by calculating the Bader charge density difference of thiourea on Pb surface and its interaction with Pb2+. Meanwhile, the effects of thiourea on the electrochemical behavior of lead electrodeposition were investigated by cyclic voltammetry and chronoamperometry. The nucleation and growth of Pb follow 3D diffusion-controlled progressive nucleation at the low potential and high thiourea concentration but follow 3D diffusion-controlled instantaneous nucleation at the high overpotential. The appropriate concentration of thiourea could improve the surface morphology of lead coating and make the layer flat and dense. The influence of thiourea on the crystalline orientation and grain size of the coating was analyzed, which indicated that the increase of thiourea concentration favored the formation of the Pb (220) crystal plane and the decrease of grain size. [Display omitted] [ABSTRACT FROM AUTHOR]

Developing transitional metal-based electrocatalysts with outstanding oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) performance is essential for energy-efficiency alkaline water electrolysis. Herein, a group of heterostructured electrocatalysts constructing of nickel-based hydroxide (NiX(OH) x , X = Co, Fe) nanosheets decorated on copper phosphide nanowires arrays，were fabricated. Both of the as-prepared NiCo(OH) x -CuP/CF and NiFe(OH) x -CuP/CF present outstanding HER and OER activity, with the overpotential of 79 and 202 mV to deliver 10 mA cm−2, respectively, along with considerable long-term stability. Encouragingly, the NiCo(OH) x -CuP/CF ǀǀ NiFe(OH) x -CuP/CF couple enables sustainable alkaline water electrolysis and powered by a solar-powered system. In-depth analyses elucidate that owing to the modulated heterogeneous interfacial states, both of the catalytic kinetics can be optimized targeting HER and OER, respectively. More significantly, a regulated electrode-electrolyte microenvironment induced by unique arrays nanostructure efficiently promote the electron-mass transfer capacity, thereby facilitating the catalytic activity expression. This work demonstrates the desirable catalytic performance by rationally designing of hydroxide-phosphide heterostructure, and highlights the structural features on catalytic performance promotion. • A delicate NiCo(OH) x -CuP/CF and NiFe(OH) x -CuP/CF catalysts were fabricated, in which the heterogeneous interfacial synergy effect between copper phosphide and nickel-based hydroxide enables the catalytic performance breakthrough. • The modulation of current distribution for the HER and OER optimizing the reaction kinetics, is achieved by interfacial synergy effect between Cu 3 P and nickel-based hydroxide. • The arrays nanostructure features high active area, good electrical conductivity, while also regulate the interfacial microenvironment between electrocatalysts and electrolyte that facilitates electro-mass transfer. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synergistic effect of Rhodamine B (RhB) was illustrated to explain the strong suppressing ability of RhB during the reduction of cupric ions. • The strong suppressing influence of RhB was confirmed by electrochemical tests. • Proper RhB is conducive to improving surface morphology and smoothness of copper interconnect layer. • Microvias filling for different blind vias radius is achieved with RhB concentration ranging from 50 mg/L to 150 mg/L. Achieving void-defect copper filling by electrodeposition on microvias is essentially important. Rhodamine B (RhB) is of excellent suppressing ability based on electrochemical analysis. Convection-dependent adsorption analysis demonstrates that 100 mg/L was the optimum value to achieve bottom-up growth. The interaction among sodium 3,3′-dithiodipropane sulfonate, polyethylene glycol, and RhB was investigated and competition adsorption between RhB and SPS is observed. Meanwhile, copper electrodeposition obeys 3D diffusion-controlled progressive nucleation process at low potential but obeys 3D diffusion-controlled instantaneous nucleation process at high overpotential. Density functional theory and in situ Raman spectra were used to study the adsorption behavior of RhB. The calculated results indicates that RhB can effectively increase the energy barrier during copper electrodeposition. The surface morphology is improved and surface roughness is lowered with proper RhB concentration. The influence of RhB on orientation and grain size was analyzed and proper RhB (100 mg/L) is conducive to the formation of Cu (1 1 1) surface and lowering the grain size. Besides, the introduction of RhB can improve the wettability, which is conducive to the bottom-up growth. The electroplating process is optimized and void-defect copper interconnect line with high quality is obtained. [ABSTRACT FROM AUTHOR]

Transparent conductors (TCs) are materials, which are characterized by high transmission of light and simultaneously very high electrical DC conductivity. These materials play a crucial role, and made possible numerous applications in the fields of electro-optics, plasmonics, biosensing, medicine, and “green energy”. Modern applications, for example in the field of touchscreen and flexible displays, require that TCs are also mechanically strong and flexible. TC can be broadly classified into two categories:uniformandnon-uniformTC. The uniform TC can be viewed as conventional metals (or electron plasmas) with plasma frequency located in the infrared frequency range (e.g. transparent conducting oxides), or ultra-thin metals with large plasma frequency (e.g. graphen). The physics of the nonuniform TC is much more complex, and could involve transmission enhancement due to refraction (including plasmonic), and exotic effects of electron transport, including percolation and fractal effects. This review ties the TC performance to the underlying physical phenomena. We begin with the theoretical basis for studying the various phenomena encountered in TC. Next, we consider the uniform TC, and discuss first the conventional conducting oxides (such as indium tin oxide), reviewing advantages and limitations of these classic uniform electron plasmas. Next, we discuss the potential of single- and multiple-layer graphene as uniform TC. In the part of the paper dealing with non-uniform metallic films, we begin with the review of random metallic networks. The transparency of these networks could be enhanced beyond the classical shading limit by the plasmonic refractive effects. The electrical conduction strongly depends on the network type, and we review first networks made of individual metallic nanowires, where conductivity depends on the inter-wire contact, and the percolation effects. Next, we review the uniform metallic film networks, which are free of the percolation effects and contact problems. In applications that require high-quality electric contact of a TC to an active substrate (such as LED or solar cells), the network performance can be optimized by employing a quasi-fractal structure of the network. We also consider the periodic metallic networks, where active plasmonic refraction leads to the phenomenon of the extraordinary optical transmission. We review the relevant literature on this topic, and demonstrate networks, which take advantage of this strategy (the bio-inspired leaf venation (LV) network, hybrid networks, etc.). Finally, we review “smart” TCs, with an added functionality, such as light interference, metamaterial effects, built-in semiconductors, and their junctions. [ABSTRACT FROM PUBLISHER]

[Display omitted] • Injection of counter ion into polymer film limits the redox processes. • The kinetic parameters strongly depends on the structure of the polymer and electrolyte composition. • Solvated counterions injection with small activation energy possible even at the temperatures as low as –40 °C. Batteries and supercapacitors are widely used in various types of portable electronic devices and electric vehicles. Typically, they retain energy and power density at room temperature and at temperatures up to +60° C. However, at sub-zero temperatures, the energy as well as the power density of the power sources dramatically decline due to the sluggish kinetics, mostly connected with solvation/desolvation processes. One of the approaches to solving the problem is using organic electrode materials, among which NiSalen-type polymers may be considered as one of the prospective. Here, we investigate the kinetic restrictions of the redox processes in such polymers at sub-zero temperatures. Temperature-dependent relationships of the kinetic parameters of charge/discharge of poly[Ni(Salen)], poly[Ni(CH 3 Salen)] and poly [Ni(CH 3 Saltmen)] were determined in electrolyte solutions based on acetonitrile and ethyl acetate with Et 4 NBF 4 , LiClO 4 and LiTFSI salts. It was shown that injection of counter ions into the polymer film limits the redox processes, and the activation energy of the process depends on the film structure as well as electrolyte composition. Proper combination of the electrolyte and polymer ensures low-activation process of counter ion injection, which corresponds to the absence of desolvation stage. As a result, fast charge and discharge of such materials is possible at the temperatures as low as –40 °C. [ABSTRACT FROM AUTHOR]

Atomically dispersed iron-nitrogen-carbon catalysts offer great potential in oxygen reduction reaction (ORR), yet the poor exposure and low density of Fe-N x sites causes relatively low ORR activity. Herein, a zinc-assisted MgO template strategy is reported to construct porous carbon-supported Fe-N 4 sites (Fe-N-C). Iron atoms surrounded by zinc species are converted to abundant Fe-N 4 sites rather than Fe containing nanoparticles. Meanwhile, both the zinc species and the MgO template can effectively produce porous structure so as to increase the utilization of Fe-N 4 sites. Fe-N-C achieves superior ORR performance and stability in alkaline medium. Theoretical calculations manifest that Fe-N 4 sites can narrow the energy barrier for ORR. Moreover, finite element simulation exhibits the porous framework in Fe-N-C could significantly accelerate the diffusion of O 2. Therefore, Fe-N-C provides a high peak power density and superior discharge ability toward Zn-air batteries. [Display omitted] • Atomically dispersed Fe-N-C are prepared by zinc-assisted template strategy. • High density of Fe-N x and hierarchical porosity boost oxygen reduction reaction. • The porous framework of Fe-N-C could significantly accelerate the diffusion of O 2. • The catalyst exhibits an excellent performance in Zn-air batteries. [ABSTRACT FROM AUTHOR]

The reasonable design of porous structures is important but usually overlooked for nonprecious metal ORR catalysts. In this study, a facile dual melt-salt-mediated templating method is developed to prepare a Fe-N-C catalyst with tailored porous framework. The ZnCl 2 and NaCl are employed to construct abundant micropores and promote the transformation of partial micropores to mesopores, respectively, reasonably forming a 3D hierarchically porous framework. The catalyst demonstrates a satisfactory surface area (1605 m2/g), promoting mass transport and exposure of FeN 4 sites. Interestingly, the dual melt-salt templates avoid rapid loss of nitrogen during pyrolysis, thus enhancing Fe-N 4 active center density. Therefore, the obtained Fe-N-C material presents outstanding ORR performance in both alkaline and acid media, as well as good stability. The advances of this catalyst are further proved in liquid and solid-state Zn-air battery, with nice discharge stability and high peak power densities. The dual melt-salt-mediated templating strategy is developed to prepare the hierarchically porous Fe-N-C catalyst incorporated with abundant Fe-N x site. [Display omitted] • 3D hierarchically porous structure is engineered using ZnCl 2 and NaCl as templates. • The protective molten salts can sharply increase the Fe-Nx active site density. • The catalyst presents outstanding ORR activity under alkaline/acidic electrolytes. • The catalyst exhibits superior performance in practical Zn-air batteries. [ABSTRACT FROM AUTHOR]

The Zn-air battery is a promising next-generation battery because of the higher energy density and safety compared with the Li-ion battery. However, the Zn-air battery suffers from huge energy loss and poor cycling performance, which are due to the sluggish kinetics of oxygen reduction/evolution reactions (ORR/OER) and the instability of bifunctional catalysts. The state-of-the-art bifunctional catalyst is the composite of Pt and Ir/Ru oxides, which is hindered by the scarce resource and high cost. Therefore, developing low-cost and high-efficient bifunctional non-noble metal-based catalysts is essential to the deployment of Zn-air batteries. Herein, we report a dual-nitrogen-source mediated pyrolysis route to rationally design and synthesize the hybrid Co/Co–N–C bifunctional catalyst. The tailored catalyst consisting of carbon confined Co nanoparticles and atomically dispersed Co–N–C moiety is identified. Remarkably, the dual-nitrogen-source derived Co/Co–N–C catalyst demonstrates excellent electrochemical performances with a half-wave potential of 0.882 V for ORR and a potential of 1.640 V at 10 mA cm−2 for OER; reasonably, the bifunctionality of Co/Co–N–C, which is supported by the excellent self-breathing Zn-air battery performance (the maximum energy density of 897.1 Wh kg Zn −1; no obvious degradation within 167h cycling). The abundant Co-Nx sites and metallic Co nanoparticles synergistically boost the ORR and OER. Image 1 • A dual-nitrogen-source method is proposed to synthesize porous Co-based catalysts. • The dual nitrogen sources play different roles in morphology and structure control. • The hybrid carbon-confined Co nanoparticles and Co-N x sites are well tailored. • The good bifunctionality is due to the hybrid active site configuration. • Excellent performance and lifetime are obtained in a Zn-air battery. [ABSTRACT FROM AUTHOR]