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Electrocatalytic carbon dioxide reduction reaction (CO₂RR) to formic acid (HCOOH) is attracted for superfluous CO₂ removal and HCOOH production under ambient conditions. Indium-based catalysts has considered as a good candidate material for CO₂RR to HCOOH due to their environmentally friendly features. However, the catalytic efficiency is limited by the poor HCOOH Faradaic efficiency (FE) and high reaction overpotential of electrocatalyst, and the activity and stability of indium-based catalysts are unsatisfactory, especially in industrial current density that is critical for commercialization. Herein, a fiber Bi-doped In₂O₃ was synthesized through electrospinning method, and it demonstrate a FE_HCOOH of 88.2% at −1.5 V versus RHE (reversible hydrogen electrode) with partial current density of −21.8 mA cm⁻² in H type cell. Specially, the Bi-In electrocatalyst also reach the industrial current density standard, which can work at −400 mA cm⁻² current density with FE_HCOOH of 92.7% (yield of HCOOH is 6.9 mmol h⁻¹) in home-made Flow cell. Importantly, Bi-In shows 24 h long-term stability test in −300 mA cm⁻². The improvement catalytic activity of Bi-In catalyst is ascribed to the optimized electronic structure of In site, and the reduced work function value of Bi-In is beneficial for reducing the formation energy of the key *OCHO intermediates.

X. Li, H. Xin. Metal Oxides Derived from Perovskite or Spinel for the Selective Hydrogenation of α,β-Unsaturated Aldehydes: A Mini–Review, ChemCatChem, 2024; 16: e202301483.

In the main text, Table 1 and Table 2 were mistakenly deleted.

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Table 1 Mixed metal oxides with perovskite or spinel structure as supports to load noble metal NPs for the selective hydrogenation of α,β-unsaturated aldehydes.

Table 2 Mixed metal oxides with perovskite or spinel structure as catalyst precursors or as catalyst for the (transfer) hydrogenation of α,β-unsaturated aldehydes.

The present study delves into electrochemical nitrogen reduction reaction (NRR) for ammonia synthesis using borophane-supported single-atom catalysts (SACs) through density functional theory (DFT) calculations. In comparison to previously reported borophene, which serves as a potential substrate for SACs in NRR, hydrogenated borophane, especially borophane-2H(B₅H₂), not only prevents metal aggregation, resulting in stable atomically dispersed metal centers, but also enhances catalytic activity by modulating the metal's charge state. Among all candidates, atomic tungsten anchored on W₁/borophane-2H(B₅H₂) displays the most favorable NRR activity and product selectivity.

The selective, transition metal-free hydrosilylation of CO₂ to CH₂(OSiEt₃)₂ has been achieved under mild conditions and in high isolated yields (up to 90%) by using Et₃SiH and the simple, easily prepared borohydride catalyst Li⁺[HB(C₆F₅)₃]⁻. The resulting CO₂-derived bis(silyl)acetal product—whose mechanism of formation has been interrogated through detailed computational and experimental studies—can be rapidly valorized through the facile synthesis of N-heterocyclic carbenes, via their corresponding imidazolium salts. By using relatively inexpensive, isotopically enriched ¹³CO₂ this protocol can be exploited to prepare NHC isotopologues that are selectively ¹³C labelled at the key, ligating C2 position. This provides an electronically responsive ¹³C NMR spectroscopic handle with dramatically enhanced sensitivity, which can directly benefit reactivity studies in both organo- and organometallic catalysis, where NHC use is ubiquitous.

The Front Cover depicts the stages ethanol follows during its conversion to n-butanol over a bifunctional catalyst, and the use of probe molecules and spectroscopy to interrogate catalytic sites. Applying a combination of in-situ FTIR, CO₂-TPD, and operando titration, Wei Tian and José Herrera use carbon dioxide and acetic acid to identify and quantify catalytically relevant functionalities responsible for C–C couplings. Their findings indicate n-butanol formation catalyzed by MgAlO systems is regulated by α-carbon proton abstraction taking place only over strong basic centers. More information can be found in the Research Article by Wei Tian and José E. Herrera (DOI: 10.1002/cctc.202400225).

The Cover Feature points to the work of M. Laura Martínez and co-workers, who investigated the effect of incorporating cobalt oxide nanoparticles into mesoporous materials, specifically SBA-15 and mesoporous cellular foam (MCF). The catalytic activity of Co-MCF was found to be higher in the oxidation reactions of methyl phenyl sulfide, resulting in improved yields and selectivity towards sulfone formation. This enhanced performance can be attributed to the larger quantity of CoO present, which facilitates the formation of catalytically active complexes such as [Co-OOH(Co3+)]. More information can be found in the Research Article by M. Laura Martínez and co-workers (DOI: 10.1002/cctc.202400836).

The development of catalytic metallodrugs is an emerging field that may offer new approaches to cancer chemotherapeutic design. By exploiting the unique properties of transition metal complexes, in-cell catalysis can be applied to modulate the cellular redox balance as part of a multi-targeting mechanism of action. We describe the synthesis and characterization of six coordinatively unsaturated iridium(III) diamine catalysts that are stable at physiological pH in aqueous solution. Reduction of the colorimetric substrate 2,6-dichlorophenolindophenol by transfer hydrogenation under biologically compatible conditions achieved turnover frequencies up to 63 ± 2 h⁻¹ and demonstrated that the source of hydride (sodium formate) is the limiting reagent, despite being in a 1000-fold excess of the catalyst. The catalyst showed low in vivo acute toxicity in zebrafish embryos and modest in vitro potency towards cancer cells. When administered alone, the catalyst generated oxidative stress in cells (an effect that was conserved in vivo), but co-treatment with a nontoxic dose of sodium formate negated this effect. Co-treatment with sodium formate significantly enhanced catalyst potency in cancer cells (A2780 ovarian and MCF7 breast cancer cells) and drug-resistant cells (A2780cis and MCF7-TAMR1) but not in non-tumorigenic cells (MRC5), demonstrating that a redox-targeting mechanism may generate selectivity for cancer cells.

In order to alleviate the influence of greenhouse effect on global climate change, the effective utilization of CO₂ to prepare fine chemicals should be paid more attention to, however, which is greatly blocked by the catalyst with low efficiency. Here, alkali metal (Li, Na, or K) are employed as a modification aid to prepare CuO/ZrO₂ catalyst for CO₂ hydrogenation to methanol. The effects of alkali metal on physicochemical properties and catalytic activities of CuO/ZrO₂ catalyst were studied in detail by the XRD, N₂-physisorption, ICP-OES, SEM/EDS, H₂/N₂O/CO₂/NH₃-chemisorption, and evaluation test. The results verified that the use of complex combustion method enabled the uniform combination of all components in precursor. High-temperature calcination (700 °C) further enhanced the strong interaction and synergistic effect between Cu and ZrO₂. Most importantly, the introduction of alkali metal effectively altered the structure and catalytic activity of CuO/ZrO₂ catalysts. However, the selectivity to methanol increased while the CO₂ conversion decreased regardless of different kinds of alkali metal being introduced to the CuO/ZrO₂ catalysts. For example, CuO/ZrO₂ catalyst modified by K exhibited excellent performance for methanol production that 98.9% selectivity of methanol based on 8.8% conversion of CO₂ after 48 h online reaction.

The direct valorization of carbon dioxide (CO₂) into value-added chemicals offers an efficient and attractive approach to promoting carbon neutrality. Among the available methods, the electrocatalytic CO₂ reduction reaction (eCO₂RR) for producing multicarbon products (C₂₊) is gaining attention owing to its simplicity. However, achieving selective control over product formation remains a challenge. One key issue is the lack of a reliable correlation between the physicochemical properties of electrocatalytic materials and their activity and selectivity. To address this gap, we conducted a model study in which carbonized Cu_xZn_y@C materials, derived from metal-organic frameworks (MOFs), were synthesized with varying Cu/Zn ratios. The pyrolyzed bimetallic MOFs retained key properties of the original MOFs while also developing new characteristics. These subtle changes in physicochemical properties influenced product selectivity. The findings of our study revealed that higher Zn doping favors the formation of single-carbon (C₁) products, whereas it is less favorable for multicarbon (C₂₊) products. Optimizing the Cu/Zn ratio was emphasized through characterization techniques, which will help guide the design of improved electrocatalytic systems for the eCO₂RR process.

Boosting the reaction stability without sacrificing the activity and cost is extremely important but full of challenges for the RuO₂-based oxygen evolution catalysts. Herein, porous and B-site substituted Y₂[Mn_0.2Ru_0.8]₂O₇ (p-Y₂[Mn_0.2Ru_0.8]₂O₇) pyrochlore toward oxygen evolution reaction is innovatively synthesized. The formed meso-/macroporous structure can increase the specific surface area and corresponding active sites, meanwhile, Mn-substitution can modulate the electronic structure, stabilize the morphology, and reduce the dosage of Ru species. Interestingly, the p-Y₂[Mn_0.2Ru_0.8]₂O₇ performs 50 h stable operation, significantly outperforming the commercial RuO₂(CM) counterpart with less than 2 h life. Furthermore, the required overpotential to achieve 10 mA cm⁻² is only 266 mV, accompanied with favorable reaction kinetics and catalyst utilization.