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Facilitating the cleavage of a NN bond and suppressing the competition hydrogen evolution reaction is essential, and but still remains a challenge in nitrogen reduction reaction (NRR). Crystal phase tailoring is an effective approach to optimize the energy barrier during the NRR process to improve the catalytic efficiency. Herein, a boron‐doping strategy to induce phase transfer from hexagonal Mo2C to cubic Mo2C for regulating the electronic structure and catalytic properties of electrocatalysts toward NRR is reported. The B doped cubic Mo2C is found to increase the exposure of active sites, regulate the d band center of Mo for enhancing the adsorption and activation of nitrogen, and reduce the energy barrier of NRR pathway, giving rise to a high ammonia yield of 52.1 μg h−1 mg−1 at −0.6 V versus reversible hydrogen electrode under ambient conditions. More importantly, the hydrogen adsorption on the surface of electrocatalyst is significantly inhibited due to the B‐doping, further improving the faradic efficiency to 36.9%, which is 4 times that of hexagonal Mo2C (9%). This work not only sheds light on the atomic‐scale design of efficient NRR electrocatalysts, but also provides a promising avenue for synchronizing the catalytic activity and selectivity for catalytic reactions. [ABSTRACT FROM AUTHOR]

Improving Pt catalytic activity and minimizing its usage as well as enhancing its stability is highly desirable for oxidation of methanol and ammonia in the field of electrocatalysis. Herein, the nanoporous Pt with coral‐like nanowires morphology/carbon fiber cloth electrocatalyst is reported, which is synthesized via a simple electrodeposition approach using phytantriol lyotropic liquid crystals as template. The obtained electrode with 3D coral‐like Pt nanowires architecture is composed of the orderly in situ grown Pt nanowires, and each individual Pt nanowire possesses a large number of nanopores. As expected, coral‐like Pt nanowires electrodes possess high electrochemical surface area of 43.1 m2 g‐1, almost twice that (25.4 m2 g‐1) of commercial Pt/C, and thus display superior catalytic activity of 343.1 mA mg‐1 and 72.0 mA mg‐1 toward methanol and ammonia oxidation, much higher than that of the commercial Pt/C (173.7 mA mg‐1 and 26.2 mA mg‐1), respectively. Additionally, the retention rates of oxidation peak current of coral‐like Pt nanowires electrode toward both methanol and ammonia oxidation after accelerated 100 cycles test achieve 82.1% and 85.6%, respectively, indicating the excellent stability of coral‐like Pt nanowires electrode. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The effects of surface metal content of Fe-M bimetallic catalysts on CO 2 adsorption, dissociation and hydrogenation were studied by DFT. • The adsorption stability of H* is slightly impacted by the surface content of the added transition metal. • CO 2 adsorption configurations are sensitive to surface Pd content of Fe-Pd, resulting in large distinctions in adsorption stabilities. • CO 2 conversion properties are similar over Fe-Ni and Fe-Co catalysts, with CO* and HCOO* as the preferred intermediates. • CO 2 reactions exhibit big distinctions with varying surface Pd content, showing a dramatic preference towards HCOO* and CO* at R = 4/9 and 5/9. Abstract Density functional theory (DFT) calculations were performed to study CO 2 adsorption, dissociation and hydrogenation over Fe-M (M = Pd, Ni, Co) bimetallic catalysts, with a focus on probing the effect of surface content of the added transition metals to Fe. Various Fe-M bimetallic surfaces were constructed with varied surface atomic ratios of Fe/(Fe + M), based on which CO 2 and atomic H* adsorptions were systematically examined. The H* was found to be energetically favorable adsorbed at the 4-fold hollow site of Fe-M catalysts and the adsorption stability was slightly impacted by the surface content of the introduced transition metal. For CO 2 adsorption, stable bent structures adsorbed on the 4-fold hollow sites were identified on Fe-Ni and Fe-Co surfaces, no matter at which Fe-M formulations. However, on Fe-Pd surfaces, CO 2 adsorption configurations were found to be sensitive to surface Pd content, resulting in large distinctions in adsorption stabilities of CO 2 as compared to Fe-Co and Fe-Ni surfaces. CO 2 dissociation and initial hydrogenation were comparatively investigated on Fe-M bimetallic surfaces, and the calculation results demonstrated that CO 2 conversion properties are similar over Fe-Ni and Fe-Co catalysts, with CO* and HCOO* as the preferred intermediates but the barriers are still above 0.8 eV. While on Fe-Pd bimetallic surfaces, CO 2 reactions exhibit significant distinctions with varying the surface Pd content, showing a dramatic preference (E act around 0.3∼0.4 eV) towards HCOO* and CO* formation at surface Pd/(Pd + Fe) atomic ratios of 4/9 and 5/9. The superior catalytic activities of Fe-Pd catalysts are attributed to the particular surface structures and electronic features at specific bimetallic formulations which result in unique adsorption configurations of CO 2 and facilitate the stabilization of transition states in CO* and HCOO* formation pathways in CO 2 conversion. [ABSTRACT FROM AUTHOR]

[Display omitted] • A cost-saving screening criteria of TM-SA supported on 1 T'-MoS 2 for NRR is provided. • The phase transition from 1 T-MoS 2 to 1 T'-MoS 2 can be achieved by TM-SA doping. • V and Ti@1T'-MoS 2 catalysts show high activity and selectivity for NRR. Electrochemical synthesis of ammonia through nitrogen reduction reaction (NRR) is cost-effective and energy-effective compared to the conventional Haber-Bosch process. However, the slow activation kinetics of N 2 hindered the development of active and selective catalysts. In this work, we showed that transition metal (TM) single atoms anchored on monolayer molybdenum disulfide (MoS 2) with 1T phase could promote its phase transition to 1T' due to broken surface symmetry induced by TM atoms. By combining the high-throughput screening with DFT calculations in transition metals, two TM elements (V, Ti) anchored on 1T'-MoS 2 were proved to be promising candidates in N 2 fixation. The V and Ti single-atom catalyst exhibits low Gibbs free energy barrier, and Ti single-atom catalyst shows the highest selectivity towards NH 3. Moreover, the stability of single-atom TM@1T'-MoS 2 was measured with the ab initio molecular dynamics (AIMD) simulations. The density of states (DOS) and surface charge analysis were conducted to reveal the origin of improved activities. Our results pave the way to design more innovative single-atom catalysts for high-performance electrocatalytic NRR. [ABSTRACT FROM AUTHOR]

Dendrites and side reactions of Zn anodes severely restrict the application of aqueous Zn‐based batteries for grid‐scale energy storage. While surface/interface modification strategies have shown some progress in improving Zn anode reversibility, they still fall short in addressing the overall regulation and intrinsic mechanisms from the bulk‐phase perspective. Herein, a bulk‐phase composite Zn/CNTs anodes fabricated by a powder‐metallurgy‐based strategy is introduced. Benefiting from the regulation of grain boundary engineering on local electric conductivity, electric field distributions, and Zn atom absorption energy, the Zn/CNTs anodes effectively suppress dendrite growth and enhance corrosion resistance during Zn stripping/plating cycles. Symmetrical cells equipped with Zn/CNT4 anodes exhibit extended cycling stability with minimal voltage hysteresis (only 22 mV). Furthermore, the full cells incorporating Zn/CNT4 with commercial MnO2 demonstrate superior rate performance and specific capacitance retention after 500 h cycling. This breakthrough opens up new avenues for optimizing metallic anodes at the bulk phase level using powder metallurgy, enabling scalable manufacturing processes, and providing valuable insights for various metal anode systems. [ABSTRACT FROM AUTHOR]

Catalytic conversion of CO2 including hydrogenation has attracted great attention as a method for chemical fixation of CO2 in combination with other techniques such as CO2 capture and storage. Potassium is a well-known promotor for many industrial catalytic processes such as in Fischer–Tropsch synthesis. In this work, we performed density functional theory (DFT) calculations to investigate the effect of potassium on the adsorption, activation, and dissociation of CO2 over Fe(100), Fe5C2(510) and Fe3O4(111) surfaces. The function of K was analyzed in terms of electronic interactions between co-adsorbed CO2 and K-surfaces which showed conspicuous promotion in the presence of K of the adsorption and activation of CO2. The adsorption strength of CO2 on these surfaces ranks as oct2-Fe3O4(111) ＞ Fe(100) ＞ Fe5C2(510). Generally, we observed a direct proportional correlation between the adsorption strength and the charges on the adsorbates. Adding K on the catalyst surface also reduces the kinetic barrier for CO2 dissociation. CO2 dissociation is more facile to occur on Fe(100) and Fe5C2(510) in the presence of K whereas the Fe3O4(111) surfaces impede CO2 dissociation regardless of the existence of K. Instead, a stable CO3− species is formed upon CO2 adsorption on Fe3O4(111) which will be directly hydrogenated when sufficient H* are available on the surface. Our results highlight the origin of the promotion effect of potassium and provide insight for the future design of K-promoted Fe-based catalysts for CO2 hydrogenation. [ABSTRACT FROM AUTHOR]

Along with the developments of large-scale energy storage system, Zn–Ni battery has received much attention. However, the poor cycling life and shelf life of Zn–Ni battery strongly limit its practical application. Herein, a solid-state functionalized composite (FC) separator was developed through a simple strategy to steadily regulate the anode-electrolyte interface characteristics to comprehensively improve the performance of Zn–Ni battery. FC separator has interaction with anode to guide even Zn deposition during cycling. As a result, the battery assembled with FC separator achieves superb cycling life of 1435 h (848th cycle). In addition, under the function of the PAAK from FC separator, hydrogen evolution reaction can be mitigated. The water retention ability has also been improved to ensure good storage performance, in which the battery exhibits an open circuit voltage higher than 1.63 V after 618 h at a high temperature of 60 °C. Besides, the negative effect brought by oxygen from cathodes has been reduced. Consequently, the battery keeps a high discharge capacity without breakdown for more than 800 h floating charge at 60 °C. The results demonstrate the large potentials for use in next-generation Zn–Ni batteries. [Display omitted] • A stable interface engineering is realized through a novel functional separator. • The separator exhibits stronger attraction to Zn to guide its deposition behavior. • The separator and the modified anode interface mitigate the side reactions. • The water retention ability is enhanced for long-term storage. • Zn–Ni battery has an impressive long cycling life and achieves significantly improved shelf life under 60℃. [ABSTRACT FROM AUTHOR]

Zr 2 ON 2 @NiFe LDH provides a large electrochemical surface area and multiple active sites due to the heterojunction structures and the interfacial synergy between NiFe LDH and Zr 2 ON 2 , enhancing bifunctional catalytic performance with a Δ E of 0.73 V, as well as improved stability for 443 h at 5 mA cm−2 in Zn-air batteries. [Display omitted] The development of a highly efficient, stable, and low-cost bifunctional catalyst is imperative for facilitating the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). However, significant challenges are involved in extending its applications to rechargeable zinc-air batteries. This study presents a bifunctional catalyst, Zr 2 ON 2 @NiFe layered double hydroxide (LDH), that was developed by utilizing a urea-glass route for synthesizing the Zr 2 ON 2 precursor, followed by riveting NiFe LDH nanosheets using a hydrothermal method. Specifically, the vertical distribution of NiFe LDH on the Zr 2 ON 2 surface ensures the maximization of the number of accessible active sites and interfacial catalysis of NiFe LDH. Notably, Zr 2 ON 2 @NiFe LDH demonstrates ORR and OER bifunctional electrocatalytic behavior and high stability owing to its heterostructure and composition. Furthermore, a rechargeable zinc-air battery using a Zr 2 ON 2 @NiFe LDH electrocatalyst as the air cathode demonstrated a high peak power density (172 mW cm−2) and galvanostatic charge-discharge cycle stability (5 mA cm−2 over 443 h). Thus, this study presents an efficient and cost-effective strategy for the design of bifunctional electrocatalysts. [ABSTRACT FROM AUTHOR]