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Reducing the use of fossil fuels is critical to human society. In recent years, electrocatalytic carbon dioxide (CO2) reduction has attracted widespread attention. A suitable CO2 reduction catalyst is essential to convert CO2 into more valuable chemical products with high selectivity and efficiency. In this paper, a highly selective ZnAlCe-Ternary metal hydroxides (ZnAlCe-THs) nanocomposite electrocatalyst material was designed and prepared, and its performance as an electrocatalyst for catalytic reduction of CO2 to carbon monoxide (CO) was explored. The layered structure of ZnAlCe-THs nanocomposites facilitates electron transfer as well as CO2 and proton transfer, providing a high specific surface area for the electroactive sites of the electrocatalytic reduction reaction. At the same time, the ZnAlCe-THs catalyst generates CO at an overpotential of − 0.5 V. At − 1.2 V versus the reversible hydrogen electrode (vs. RHE), the bias current density is about 10.46 mA cm−2 with high selectivity of 89.3% Faraday efficiency. Its excellent electrochemical properties make it a good catalyst for the selective reduction of CO2 to CO. In this paper, ZnAlCe-Ternary mental hydroxides (ZnAlCe-THs) with a layered hydrotalclike structure were prepared by hydrothermal and co-precipitation methods. It showed excellent catalytic performance in the electrocatalytic reduction of carbon dioxide to carbon monoxide with a Faraday efficiency of 89.3% at − 1.2 V vs. RHE and a current density of 10.46 mA cm−2 for higher selectivity for CO. In addition, the ZnAlCe-THs catalyst is stable and it can operate for 5 h without particularly significant deactivation. [ABSTRACT FROM AUTHOR]

The electrocatalytic carbon dioxide reduction reaction (CO2RR) is considered as a promising approach for simultaneous CO2 treatment and production of value-added chemicals. Bismuth has been demonstrated as a fascinating electrocatalyst for selective conversion of CO2 to HCOOH. In this study, we comprehensively investigated the effects of size, morphology, and carbon supports on the CO2RR performance of Bi catalysts to enhance their electrocatalytic CO2RR activity and HCOOH selectivity. Specifically, Bi nanospheres with varying sizes were synthesized by adjusting the amount of polyvinylpyrrolidone (PVP), achieving similar selectivity for HCOOH but increasing current density with decreasing size. Bi nanoplates and Bi nanoflowers were also prepared through the reduction of BiOCl precursors, with Bi nanoflowers demonstrating a superior morphology compared to other Bi nanocrystals while achieving a HCOOH faradaic efficiency (FEHCOOH) of 95% at −1.6 V vs. SCE and excellent durability over 12 hours. The predominance of *HCOO intermediates in the in situ ATR-SEIRA spectra indicates that during the CO2RR, Bi nanoflowers primarily followed the pathway leading to HCOOH production. Furthermore, incorporation of Ketjenblack into the synthesis process resulted in carbon-supported Bi catalysts, which exhibited approximately 20% enhancement in FEHCOOH within a wide potential range from −1.3 V to −1.8 V vs. SCE due to an improved separation effect and electron transfer capacity provided by carbon materials. [ABSTRACT FROM AUTHOR]

Utilizing renewable electricity for the electrocatalytic conversion of CO2 into alcohols represents a promising avenue for generating value‐added fuels and achieving carbon neutrality. Recently, there has been growing scientific interest in achieving high‐efficiency conversion of CO2 to alcohols, with significant advancements made in mechanism understanding, reactor design, catalyst development, and more. Herein, a thorough examination of the latest advances in electrocatalytic CO2 reduction reaction (CO2RR) to alcohols is provided. General mechanisms and pathways of electrocatalytic conversion of CO2‐to‐alcohols are systematically illustrated. Subsequently, electrolyzer configurations, electrolytes, and electrocatalysts employed in CO2RR are summarized. After that, critical operating parameters (e.g., reaction pressure, temperature, and pH) that would significantly influence the CO2RR process are also analyzed. Finally, the review addresses challenges and offers perspectives in this field to guide future studies aimed at advancing CO2‐to‐alcohols conversion technologies. [ABSTRACT FROM AUTHOR]

A homogeneous electrochemical deposition method was used in this study of CdAl nanoparticles onto CP fibers at −1.1, −1.2, −1.3, and −1.4 V vs. RHE to prepare highly active, selective, and stable CdAl-LDHs nanocatalysts. The electrochemically deposited materials exhibited extremely high CO selectivity during CO 2 RR, with the CO FE reaching 99.71% at −1.6 V vs. RHE and a partial current density of 22.13 mA cm−2. The CdAl-LDHs maintained excellent CO FE along with high CO partial current density. Remarkably, the CdAl-LDHs demonstrated outstanding electrochemical performance that exceeded most of the reported CO 2 reduction to CO electrocatalysts, maintaining stable electrocatalytic performance for more than 30 h with the FE remaining stable at about 99% and a current density at 10.05 mA cm−2 with little decay. [Display omitted] • CdAl nanoparticles with high activity, selectivity and stability were directly deposited on CP fibers by electrochemical deposition method. • The materials prepared by electrochemical deposition exhibit extremely high CO selectivity in the CO 2 RR process, with Faraday efficiency up to 99.71 %. • CdAl-LDHs can maintain the electrocatalytic performance for more than 30 h, and in this process, and the Faraday efficiency can be stable at about 99 %. Layered bimetallic hydroxides are at the forefront of current research in electrocatalytic materials. Although there is considerable research on various bimetallic hydroxides, the study of bimetallic hydroxides for electrocatalytic reduction of carbon dioxide is limited. In this paper, cadmium-aluminum layered bimetallic hydroxide nanoparticles (CdAl-LDHs) were prepared using a simple electrochemical deposition method. The prepared CdAl-LDHs was characterized in detail, and its potential application as an electrocatalyst was discussed. CdAl-LDHs prepared using different methods showed different selectivity in the electrocatalytic reduction of CO 2 to CO. The nanomaterial exhibits excellent CO selectivity in a reaction chamber using 2 %-BMIM(PF 6)(1-butyl-3-methylimidazolium hexafluorophosphate)/DMF(N-N dimethyl formamide) as the electrolyte. The CdAl-LDHs prepared by electrochemical deposition exhibited a maximum CO partial current density of 22.13 mA cm−2 with a remarkable CO Faraday efficiency (FE) of 99.71 %, which is comparable to or even higher than that of noble metal catalysts. This high selectivity for CO indicates its potential as an alternative to expensive noble metal catalysts. Moreover, the catalyst demonstrated high stability over 30 h of continuous operation with stable FE of around 99 % and a current density of around 10.5 mA cm−2, with minimal degradation during the entire reaction cycle. In addition, the catalyst showed a low HER current density of less than 0.1 mA cm−2 at all tested potentials, indicating that the catalyst maintains a high level of CO 2 conversion over the entire range of tested potentials. This suggests its great potential for industrial applications. [ABSTRACT FROM AUTHOR]

In recent decades, significant progress has been achieved in rational developments of electrocatalysts through constructing novel atomistic structures and modulating catalytic surface topography, realizing substantial enhancement in electrocatalytic activities. Numerous advanced catalysts were developed for electrochemical energy conversion, exhibiting low overpotential, high intrinsic activity, and selectivity. Yet, maintaining the high catalytic performance under working conditions with high polarization and vigorous microkinetics that induce intensive degradation of surface nanostructures presents a significant challenge for commercial applications. Recently, advanced operando and computational techniques have provided comprehensive mechanistic insights into the degradation of surficial functional structures. Additionally, various innovative strategies have been devised and proven effective in sustaining electrocatalytic activity under harsh operating conditions. This review aims to discuss the most recent understanding of the degradation microkinetics of catalysts across an entire range of anodic to cathodic polarizations, encompassing processes such as oxygen evolution and reduction, hydrogen reduction, and carbon dioxide reduction. Subsequently, innovative strategies adopted to stabilize the materials' structure and activity are highlighted with an in-depth discussion of the underlying rationale. Finally, we present conclusions and perspectives regarding future research and development. By identifying the research gaps, this review aims to inspire further exploration of surface degradation mechanisms and rational design of durable electrocatalysts, ultimately contributing to the large-scale utilization of electroconversion technologies. [ABSTRACT FROM AUTHOR]

As an important strategic resource, rare earths (REs) constitute 17 elements in the periodic table, namely 15 lanthanides (Ln) (La–Lu, atomic numbers from 57 to 71), scandium (Sc, atomic number 21) and yttrium (Y, atomic number 39). In the field of catalysis, the localization and incomplete filling of 4f electrons endow REs with unique physical and chemical properties, including rich electronic energy level structures, variable coordination numbers, etc., making them have great potential in electrocatalysis. Among various RE catalytic materials, rare earth oxide (REO)-based electrocatalysts exhibit excellent performances in electrocatalytic reactions due to their simple preparation process and strong structural variability. At the same time, the electronic orbital structure of REs exhibits excellent electron transfer ability, which can reduce the band gap and energy barrier values of rate-determining steps, further accelerating the electron transfer in the electrocatalytic reaction process; however, there is a lack of systematic review of recent advances in REO-based electrocatalysis. This review systematically summarizes the synthesis, properties and applications of REO-based nanocatalysts and discusses their applications in electrocatalysis in detail. It includes the hydrogen evolution reaction (HER), oxygen evolution reaction (OER), hydrogen oxidation reaction (HOR), oxygen reduction reaction (ORR), carbon dioxide reduction reaction (CO2RR), methanol oxidation reaction (MOR), nitrogen reduction reaction (NRR) and other electrocatalytic reactions and further discusses the catalytic mechanism of REs in the above reactions. This review provides a timely and comprehensive summary of the current progress in the application of RE-based nanomaterials in electrocatalytic reactions and provides reasonable prospects for future electrocatalytic applications of REO-based materials. [ABSTRACT FROM AUTHOR]