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A proof-of-concept study is undertaken to demonstrate the utility of the machine learning combined with the thermodynamic perturbation theory (MLPT) to test the accuracy of electronic structure methods in finite-temperature thermodynamic calculations. As a test example, formic acid dimer is chosen, which is one of the systems included in the popular benchmark set S22 [Jurečka et al., Phys. Chem. Chem. Phys. 8, 1985–1993 (2006)]. Starting from the explicit molecular dynamics and thermodynamic integration performed at the PBE + D2 level, the MLPT is used to obtain fully anharmonic dimerization free and internal energies at the reference quality CCSD(T) level and 19 different density functional approximations, including GGA, meta-GGA, non-local, and hybrid functionals with and without dispersion corrections. Our finite-temperature results are shown to be both qualitatively and quantitatively different from those obtained using the conventional benchmarking strategy based on fixed structures. The hybrid functional HSE06 is identified as the best performing approximate method tested, with the errors in free and internal energies of dimerization being 36 and 41 meV, respectively. [ABSTRACT FROM AUTHOR]

In the mirabegron (MIR) synthesis, the N‐nitroso mirabegron (NNM) is obtained during synthetic process of MIR; water is being used in reaction under acidic condition. Nitrite source is from water, and secondary amine source is from MIR as it has secondary amine; NNM is generated as an impurity during the synthesis of MIR. The presence of NNM in MIR could potentially affect its effectiveness. The purpose of this study was to establish a Ultra‐performance liquid chromatography‐mass spectrometry/mass spectrometry (UPLC‐MS/MS) methodology to identify NNM in MIR samples. The method for NNM analysis was developed on Acquity HSS T3 (100*2.1) mm 1.8 μm column with gradient elution using mobile phase consisted of 0.1% formic acid in water (mobile phase A) and 0.1% formic acid in methanol (mobile phase B). Mass spectrometer with electrospray ionization operated in the MRM mode was used in the analysis of NNM (m/ z 426.20 → 170.00). The UPLC‐MS/MS methodology proposed showed a good linearity (0.02 to 0.72 ppm), good system precision (RSD = 0.57%), good method precision (RSD = 0.87%), acceptable accuracy (94.5–116.5%), low detection limit (0.006 ppm) and low quantification limit (0.02 ppm) for NNM. The UPLC‐MS/MS methodology proposed can be utilized to assess the quality of MIR sample for the presence of NNM impurity. [ABSTRACT FROM AUTHOR]

The photocatalytic hydrolysis reaction primarily unfolds on the material's surface, making the material's morphology and microstructure critical for the catalytic efficiency of photocatalysts. In this paper, a formic acid-assisted melamine hydrothermal self-assembly method is explored to prepare g-C 3 N 4 photocatalysts with a unique morphology. The impact of sintering temperature on the morphology of the g-C 3 N 4 photocatalysts are explored and the effect of formic acid concentration on the XRD and FTIR was analyzed. Findings reveal that the g-C 3 N 4 nanostructures photocatalyst possesses fibrous tubular and nanosheet structures, boasting a heightened specific surface area (32.9 m2/g) and a more refined graphite-like crystalline framework. When synthesized with a 0.15 M concentration of formic acid, the g- C 3 N 4 nanostructured photocatalyst achieved a hydrogen production rate (1289.4 μmol h−1 g−1), which is approximately 4.8 times greater than that of bulk g-C 3 N 4 (264.7 μmol h−1 g−1). This work provides a simple method for preparing high-performance g-C 3 N 4 based photocatalysts for visible light hydrolysis hydrogen production. [ABSTRACT FROM AUTHOR]

CO2 conversion into chemicals is of paramount importance in the valorization of CCU processes; therefore, studying various chemical synthesis pathways is indispensable to investigate their feasibility and sustainability. In this work, thermo-catalytic and electrochemical reduction routes of formic acid production processes using CO2 were analyzed for comparative techno-economic viability and environmental friendliness compared to the conventional route under different scenarios with a consistent set of assumptions, methodology and level of details. The thermo-catalytic pathway revealed consistently lower levelized cost of production (LCP) in all the examined scenarios compared to the electrochemical reduction pathway. The best-case scenario of the thermo-catalytic pathway also indicated that the thermo-catalytic pathway can be a competitive alternative to the conventional pathway with a slightly lower LCP (1.05%) and considerably lower carbon footprint (38.8%). The thermo-catalytic pathway consistently demonstrated lower carbon footprint results compared to both the conventional and electrochemical reduction pathways. For instance, the base-case thermo-catalytic pathway showed 38.8% and 68.5% lower carbon footprints compared to the conventional and electrochemical pathways, respectively. Notably, the CO2 source significantly affected the global warming index (GWI) compared to the sources of H2 and electricity for the thermo-catalytic pathway. However, the electricity source significantly affected the GWI compared to the CO2 source for the electrochemical reduction pathway. [ABSTRACT FROM AUTHOR]

A copper porphyrin‐derived metal–organic framework electrocatalyst, FICN‐8, was synthesized and its catalytic activity for CO2 reduction reaction (CO2RR) was investigated. FICN‐8 selectively catalyzed electrochemical reduction of CO2 to CO in anhydrous acetonitrile electrolyte. However, formic acid became the dominant CO2RR product with the addition of a proton source to the system. Mechanistic studies revealed the change of major reduction pathway upon proton source addition, while catalyst‐bound hydride (*H) species was proposed as the key intermediate for formic acid production. This work highlights the importance of electrolyte composition on CO2RR product selectivity. [ABSTRACT FROM AUTHOR]

Arbitrary disposal of plastic waste into landfills and oceans can disturb the ecological system and even challenge human survival. Centralized plastic recycling process only works for selected types of plastics (e.g., polyethylene) with limited contribution (<10%), because of high infrastructure requirement. Comparatively, photoreforming of plastic waste for commodity and fuels production is much more facile and decentralizable, and thus holds great potential to mitigate the plastic waste challenge. To this end, a fully solar powered photoelectrochemical system is developed to selectively upgrade polyimide waste (often appears in electronic waste) into valuable commodity chemicals, including succinic acid, acetic acid, and formic acid, and cogenerating green hydrogen fuels. It is also demonstrated that one of the key monomer, pyromellitic acid, and the precious metals (in electronic waste) can be fully recycled. This proof‐of‐concept demonstration provides a new viewpoint for designing decentralized photoelectrochemical system for simultaneous plastic waste upcycling and renewable fuel synthesis, critical for a sustainable plastic economy. Selective cleavage of benzene ring also opens a green route for other benzene ring‐containing waste upgrading. [ABSTRACT FROM AUTHOR]

With the increasing focus on sustainable development, the exploration of renewable and environmentally friendly resources for product synthesis has become paramount. This study aims to investigate the production of dihydroxystearic acid through the in situ hydrolysis of epoxidized oleic acid. Epoxidation of oleic acid was achieved through the utilization of in situ generated performic acid, resulting in the production of epoxidized oleic acid. The synthesis of performic acid involved the combination of formic acid as an oxygen carrier and hydrogen peroxide as an oxygen donor. A maximum epoxide yield of 65% was attained at an optimum reaction time of 30 min. Hydrochloric acid was found to be the most efficient catalyst. A kinetics study was also done using the genetic algorithm to find the reaction rate of dihydroxystearic acid production. The difference between simulation and experimental results was less than 0.1%, which is insignificant. The findings highlight the potential of utilizing renewable resources for the synthesis of high-value compounds, promoting a greener and more sustainable future. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pd/DUT-67-PZDC(10) catalyst with highly dispersed Pd NPs was prepared. • The hierarchically microporous structural property of the DUT-67-PZDC support is beneficial for the stabilization of Pd NPs. • The dual N sites on the DUT-67-PZDC(10) support could act as excellent proton buffers to stimulate the O-H bond cleavage in FA. • The ultrasmall size (1.7 nm) and high dispersion of Pd NPs could expose more catalytic active sites. • The Pd/DUT-67-PZDC(10) catalyst shows an initial TOF value of 2572h−1, 100 % FA conversion and H 2 selectivity, and excellent stability at 60 °C. The highly dispersed ultrasmall palladium nanoparticles (Pd NPs) (1.7 nm) were successfully immobilized on a N -containing metal–organic framework (MOF, DUT-67-PZDC) using a co-reduction method, and it is used as an excellent catalyst for formic acid dehydrogenation (FAD). The optimized catalyst Pd/DUT-67-PZDC(10, 10 wt% Pd loading) shows 100% hydrogen (H 2) selectivity and formic acid (FA) conversion at 60 °C, and the commendable initial turnover frequency (TOF) values of 2572 h−1 with the sodium formate (SF) as an additive and 1059 h−1 even without SF, which is better than most reported MOF supported Pd monometallic heterogeneous catalysts. The activation energy (Ea) of FAD is 43.2 KJ/mol, which is lower than most heterogeneous catalysts. In addition, the optimized catalyst Pd/DUT-67-PZDC(10) maintained good stability over five consecutive runs, demonstrating only minimal decline in catalytic activity. The outstanding catalytic performance could be ascribed to the synergistic corporations of the unique structure of DUT-67-PZDC carrier with hierarchical pore characteristic, the metal-support interaction (MSI) between the active Pd NPs and DUT-67-PZDC, the highly dispersed Pd NPs with ultrafine size serve as the catalytic active site, as well as the N sites on the support could act as the proton buffers. This work provides a new paradigm for the efficient H 2 production of FAD by constructing highly active heterogeneous Pd-based catalysts using MOF supports. [ABSTRACT FROM AUTHOR]

BACKGROUND: A material of natural origin, clinoptilolite, was modified with selected metals in order to obtain a catalyst for the conversion of xylose – the main component of the hemicellulose fraction present in lignocellulosic biomass – to selected carboxylic acids. RESULTS: The starting material without modification (0‐parent), the hydrogen form (0‐hydrogen) of zeolite and zeolite after hierarchization with hydrochloric acid (0‐dealuminated) were used. Iron, copper and cobalt ions were introduced as active centers using the sonication technique. The catalytic process was carried out in a pressure autoclave for 2 h at a temperature of 220 °C. Compounds such as formic acid with a yield of 91% (0‐parent) and lactic acid with a yield of 66.1% (Fe‐hydrogen) were obtained. Conclusion: The catalytic processes carried out using xylose lead to the obtaining of a mixture of carboxylic acids: lactic acid, pyruvic acid and formic acid. An important role here is played by the presence of iron as an active site, which leads to the transformation of xylose into lactic acid by dehydration, and the presence of Lewis and Brønsted active sites. In the case of formic acid, which has never been reported in publications on a similar topic, the starting zeolite without modification contributed to its preparation. It is possible that the content of alkali metals contributed to its preparation along with the coupling of the oxidation reaction of the intermediate product, because of the presence of small amounts of iron, which are present in the natural material. © 2024 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

The photocatalytic reduction of CO2 into formic acid is a feasible approach to alleviate the effects of global climate change and achieve chemical energy storage. It is important to design highly active photocatalysts to improve the selectivity and yield of formic acid. In this study, TiO2-based catalysts were prepared and loaded with Pd nanoparticles via an impregnation process. The Pd/H-TiO2 catalyst demonstrated superior CO2 reduction activity and a high formic acid production rate of 14.14 mmolcat·g−1·h−1. The excellent catalytic performance observed in the presence of a Pd/H-TiO2 catalyst is ascribed to the synergy between Ov and Pd. The presence of Ov led to increase in CO2 adsorption while Pd loading enhanced the photogenerated electron-hole pair separation. Electron transfer from H-TiO2 to Pd also contributed to CO2 activation. [ABSTRACT FROM AUTHOR]

Wearable strain transducers are poised to transform the field of healthcare owing to the promise of personalized devices capable of real‐time collection of human physiological health indicators. For instance, monitoring patients' progress following injury and/or surgery during physiotherapy is crucial but rarely performed outside clinics. Herein, multifunctional liquid‐free ionic elastomers are designed through the volume effect and the formation of dynamic hydrogen bond networks between polyvinyl alcohol (PVA) and weak acids (phosphoric acid, phytic acid, formic acid, citric acid). An ultra‐stretchable (4600% strain), highly conducting (10 mS cm−1), self‐repairable (77% of initial strain), and adhesive ionic elastomer is obtained at high loadings of phytic acid (4:1 weight to PVA). Moreover, the elastomer displayed durable performances, with intact mechanical properties after a year of storage. The elastomer is used as a transducer to monitor human motions in a device comprising an ESP32‐based development board. The device detected walking and/or running biomechanics and communicated motion‐sensing data (i.e., amplitude, frequency) wirelessly. The reported technology can also be applied to other body parts to monitor recovery after injury and/or surgery and inform practitioners of motion biomechanics remotely and in real time to increase convalescence effectiveness, reduce clinic appointments, and prevent injuries. [ABSTRACT FROM AUTHOR]

Highlights With the rapid development of modern transportation systems, optimizing the relationship between structure and performance to obtain natural rubber‐based nanocomposites with excellent comprehensive performance is still worth to investigation. Herein, the regulation of flocculation potential through different flocculants selection on the thermomechanical properties for carbon black/graphene oxide reinforced natural rubber (CB/GO/NR) nanocomposites were investigated based on the compression electric double layer theory. The results showed that formic acid owned the highest zeta potential with comparison of sodium chloride (NaCl), calcium chloride (CaCl2), and aluminum chloride (AlCl3). Meanwhile, as the content was 8 wt%, tensile strength, tearing strength and thermal conductivity could achieve to 27.64 MPa, 56.89 N/mm, and 1.05 W m−1 K−1, respectively. While the heat generation after compression fatigue dropped to 10.1°C. These findings reveal that the highest zeta potential of formic acid could promote the improvement of flocculation degree between GO and NR latex and significantly enhanced the thermomechanical properties of CB/GO/NR nanocomposites due to the larger flocculation potential difference. Therefore, this study not only provides important theoretical insights for preparing high‐performance NR‐based nanocomposites, but also highlights the crucial role of high zeta potential flocculants in optimizing the composite performance. More importantly, the findings offer the creative insights for preparation of the excellent comprehensive NR nanocomposites for the practical industry application. The effect of flocculation degree on the properties of CB/GO/NR composites was studied. Formic acid was benefit to the flocculation and could promote the surface interaction. CB/GO/NR composites possessed the improved thermal and mechanical properties. [ABSTRACT FROM AUTHOR]

Rationale: Nirmatrelvir is a protease inhibitor that is essential for virus replication. Nirmatrelvir is indicated for the management of mild to severe cases of COVID‐19 in individuals who are 12 years of age or older. Forced degradation studies of nirmatrelvir were carried out on the drug substance in solid and solution forms, subjecting it to various stress conditions according to International Conference on Harmonisation (ICH) Q1A(R2) and Q1B guidelines. The analytical method was validated as per the ICH Q2(R1) guidelines. Methods: The drug substance (nirmatrelvir) was subjected to hydrolysis (acidic, alkaline, and neutral), thermal, photolytic, and oxidative stress conditions. Five degradation products (DPs) of nirmatrelvir formed under hydrolytic (acidic and alkaline) and oxidative (2,2‐azobisisobutyronitrile) stress conditions. These degradation products were identified and separated using reverse‐phase HPLC on a phenomenex kinetex C8 column (250 mm × 4.6 mm × 5 μm) with gradient elution. The mobile phase consisted of 0.1% formic acid and acetonitrile, and detection was carried out at a wavelength of 210 nm. Results and conclusions: Nirmatrelvir and its five DPs were efficiently separated using reverse phase–HPLC. These five DPs were identified and characterized using LC‐electrospray ionization (ESI)‐Q‐TOF‐coupled mass spectrometry analysis in the ESI‐positive ionization mode. The formation mechanisms of the DPs and the most probable mass fragmentation pathways for both nirmatrelvir and its DPs were elucidated. The developed method demonstrated selectivity, accuracy, linearity, and reproducibility, making it appropriate for quality control of nirmatrelvir and future research studies. Additionally, the physicochemical and Absorption, Distribution, Metabolism, Excretion, and Toxicity (ADMET) properties of nirmatrelvir and its DPs were predicted using ADMET predictor software. The toxicity profile revealed that DP2 and DP3 have teratogenic effects while DP1 and DP3 caused phospholipidosis. [ABSTRACT FROM AUTHOR]

Furfural is an attractive bio‐based platform chemical that has many derivatives of commercial interest. Herein, we show that the selectivity of the direct furfural reduction can be steered from 2‐methylfuran and 2‐methyltetrahydrofuran to furfuryl alcohol and tetrahydrofurfuryl alcohol by varying the ratio of formic acid and sodium formate. These reagents take the role of terminal reductants in the disclosed heterogeneous Pd‐catalysed process. We report the development and optimisation of the reaction conditions for three different products directly from furfural: 2‐methyltetrahydrofuran, tetrahydrofurfuryl alcohol and 2‐methylfuran which were obtained in 59 %, 46 %, and 63 % selectivity, respectively. Furthermore, the protocol uses commercially available Pd/Al2O3 as catalyst and the formic acid and sodium formate can be obtained from biogenous sources. [ABSTRACT FROM AUTHOR]

Covalent heptazine frameworks (CHFs) are widely utilized in the recent years as potential photocatalysts. However, their limited conjugated structures, low crystallinity and small surface areas have restricted the practical photocatalysis performance. Along this line, we report herein the synthesis of a kind of mixed crystalline CHF (m‐CHF‐1) with built‐in heterojunction structure, which can efficiently catalyze the formic acid dehydrogenation by visible light driven photocatalysis. The m‐CHF‐1 is synthesized from 2,5,8‐triamino‐heptazine and dicyanobenzene (DCB) in the molten salts, in which DCB plays as organic molten co‐solvent to promote the rapid and ordered polymerization of 2,5,8‐triamino‐heptazine. The m‐CHF‐1 is formed by embedding phenyl‐linked heptazine (CHF−Ph) units in the poly(heptazine imide) (PHI) network similar to doping. The CHF−Ph combined with PHI form an effective type II heterojunction structure, which promote the directional transfer of charge carriers. And the integration of CHF−Ph makes m‐CHF‐1 have smaller exciton binding energy than pure PHI, the charge carriers are more easily dissociated to form free electrons, resulting in higher utilization efficiency of the carriers. The largest hydrogen evolution rate reaches a value of 42.86 mmol h−1 g−1 with a high apparent quantum yield of 24.6 % at 420 nm, which surpasses the majority of other organic photocatalysts. [ABSTRACT FROM AUTHOR]

Berries are a rich source of natural antioxidant compounds, which are essential to profile, as they add to their nutritional value. However, the complexity of the matrix and the structural diversity of these compounds pose challenges in extraction and chromatographic separation. By relying on multivariate curve resolution alternating least squares (MCR-ALS) ability to extract components from complex spectral mixtures, our study evaluates the contributions of various extraction techniques to interference, extractability, and quantifying different groups of overlapping compounds using liquid chromatography diode array detection (LC-DAD) data. Additionally, the combination of these methods extends its applicability to evaluate polyphenol degradation in stored berry smoothies, where evolving factor analysis (EFA) is also used to elucidate degradation products. Results indicate that among the extraction techniques, ultrasonication-assisted extraction employing 1% formic acid in methanol demonstrated superior extractability and selectivity for the different phenolic compound groups, compared with both pressurized liquid extraction and centrifugation of the fresh berry smoothie. Employing MCR-ALS on the LC-DAD data enabled reliable estimation of total amounts of compound classes with high spectral overlaps. Degradation studies revealed significant temperature-dependent effects on anthocyanins, with at least 50% degradation after 7 months of storage at room temperature, while refrigeration and freezing maintained fair stability for at least 12 months. The EFA model estimated phenolic derivatives as the main possible degradation products. These findings enhance the reliability of quantifying polyphenolic compounds and understanding their stability during the storage of berry products. [ABSTRACT FROM AUTHOR]

[Cp*Ir(R‐pica)Cl] (Cp*=pentamethylcyclopentadienyl anion, pica=2‐picolineamidate) complexes bearing carbohydrate substituents on the amide nitrogen atom (R=methyl‐β‐D‐gluco‐pyranosid‐2‐yl, 1; methyl‐3,4,6‐tri‐O‐acetyl‐β‐D‐glucopyranosid‐2‐yl, 2) were tested as catalysts for formic acid dehydrogenation in water. TOFMAX values over 12000 h−1 and 50000 h−1 were achieved at 333 K for 1 and 2, respectively, with TON values over 35000 for both catalysts. Comparison with the simpler cyclohexyl‐substituted analogue (3) indicated that glucosyl‐based complexes are much better performing under the same experimental conditions (TOFMAX=5144 h−1, TON=5000 at pH 2.5 for 3) owing to a lower tendency to isomerize to the less active k2‐N,O isomer upon protonation. The 5‐fold increase in TOFMAX observed for 2 with respect to 1 is reasonably due to an optimal steric protection by the acetyl substituent, which may prevent unproductive inner‐sphere reactivity. These results showcase a powerful strategy for the inhibition of the common deactivation pathways of [Cp*Ir(R‐pica)X] catalysts for FA dehydrogenation, paving the way for the development of better performing hydrogen storage systems. [ABSTRACT FROM AUTHOR]

The cathodic reduction of pressurized CO2 (PrCO2CR) at suitable cathodes can allow to produce various chemicals, such as formic acid/formate (FA) and carbon monoxide or synthesis gas, with high faradic efficiencies (FEs) and productivities. Here, we have performed the conversion of CO2 in an undivided pressurized electrochemical reactor using silver cathode in order to determine the optimal values of CO2 pressure and current density. It was found that the plot FE vs. pressure resulted in a curve with a maximum. Similarly, an optimal value of current density can be selected for the PrCO2CR. The competition between the production of carbon monoxide and formic acid/formate is strongly affected by both the pressure and the current density. Eventually the effect of pressure and current density on the economic figures of the process was evaluated. [ABSTRACT FROM AUTHOR]

AbstractThis study investigated the reduction of CO2 and its conversion into formic acid in a developed double-electrode layer trickle bed electrochemical reactor (TBER) to combat global warming. VulcanXC72 carbon black and polytetrafluoroethylene (C-PTFE) mixture was pasted on stainless steel mesh to form the cathode layers which was characterized using SEM,BET,FTIR, porosity and particles size distribution. Using K2CO3 alkaline solution, CO2 was in situ reduced over the cathode bed suggesting a renewable energy source to replace hydrocarbon fuel. The anode’s plates reduces the reactor voltage and improve the current distribution. The effect of cell voltages, gas and liquid flow rates, K2CO3 concentrations, and temperatures were systematically studied and formic acid production was predicted as well. CO2 was successfully reduced in this system and reached its maximum conversion at 94.47% in 40 min at a reduction temperature of 10 °C which is attributed to the enhancement of CO2 solubility in the electrolyte at low temperatures. At the best conditions, formic acid production increased with time and reached 266 ppm after 60 min, presenting this process as an alternative to the traditional methods. The development of a two-layer reactor working in trickling flow mode is used for the first time in such highly complex processes, where each layer acts as a separate reactor from the other layer. Moreover, to avoid using expensive metals as electrocatalysts and make the process eco-friendly, a conductive carbon black was used as an electrocatalyst. Despite this promising results, the system was designed to be scalable for industrial use and used in wastewater treatment and methane, methanol, and ammonia production. [ABSTRACT FROM AUTHOR]

A straightforward nebulized spray system is designed to explore the hydrogenation of carbon dioxide (CO2) within water microdroplets surrounded by different gases such as carbon dioxide, nitrogen, oxygen, and compressed air. The collected droplets are analyzed using water‐suppressed nuclear magnetic resonance (NMR). Formate anion (HCOO−), acetate anion (CH3COO−), ethylene glycol (HOCH2CH2OH), and methane (CH4) are detected when water is nebulized. This pattern persisted when the water is saturated with CO2, indicating that CO2 in the nebulizing gas triggers the formation of these small organics. In a pure CO2 atmosphere, the formate anion concentration is determined to be ≈70 µm, referenced to dimethyl sulfoxide, which has been introduced as an internal standard in the collected water droplets. This study highlights the power of water microdroplets to initiate unexpected chemistry for the transformation of CO2 to small organic compounds. [ABSTRACT FROM AUTHOR]

The wrinkles are pervasive in ultrathin two‐dimensional (2D) materials, but the regulation of wrinkles is rarely explored systematically. Here, we employed a series of carboxylic acids (from formic acid to octanoic acid) to control the wrinkles of Zr‐BTB (BTB=1, 3, 5‐(4‐carboxylphenyl)‐benzene) metal–organic framework (MOF) nanosheet. The wrinkles at the micrometer scale were observed with transmission electron microscopy. Furthermore, high‐angle annular dark‐field (HAADF) images showed lattice distortion in many nanoscale regions, which was precisely matched to the nano‐wrinkles. With the changes of hydrophilicity/hydrophobicity, MOF‐MOF and MOF‐solvent interactions were possibly synergistically regulated and wrinkles with different sizes were obtained, which was supported by HAADF, molecular dynamics, and density functional theory calculation. Different wrinkle sizes resulted in different pore sizes between the Zr‐BTB nanosheet interlayers, providing highly‐oriented thin films and the successive optimization of kinetic diffusion pathways, proved by grazing‐incidence wide‐angle X‐ray scattering and nitrogen adsorption. The most suitable wrinkle pore from Zr‐BTB‐C4 exhibited highly efficient chromatographic separation of the substituted benzene isomers. Our work provides a rational route for the modulation of nanoscale wrinkles and their stacked pores of MOF nanosheets and improves the separation abilities of MOFs. [ABSTRACT FROM AUTHOR]

Formic acid (HCOOH) is one of the most abundant volatile organic compounds (VOCs) in the Earth's atmosphere and an important source of atmospheric acidity. Here we present the first retrieval of HCOOH from a geostationary orbit using observations from the Geostationary Interferometric Infrared Sounder (GIIRS) on board FengYun‐4B. The results from July 2022 to June 2023 show the monthly variation of the HCOOH distribution in Asia. In addition, we show that FY‐4B/GIIRS effectively tracks HCOOH enhancements from wildfires both during the day and at night. Finally, inter‐comparison with IASI HCOOH data shows good agreement, indicating that FY‐4B/GIIRS observations have comparable sensitivity to IASI. This study is an important first step toward monitoring VOCs from geostationary infrared sounders, including the existing and future GIIRS on board the FY‐4 series and the forthcoming European geostationary infrared sounder (IRS) on board Meteosat Third Generation (MTG). Plain Language Summary: Satellite observations play an indispensable role in improving our understanding of the global sources and sinks of HCOOH, an important volatile organic compound in the atmosphere. However, existing polar‐orbiting satellites that are sensitive to tropospheric HCOOH typically provide up to two overpasses per day over the same spot, one during the day and one during the night. The diurnal variations of tropospheric HCOOH are therefore under‐constrained to track its evolution in the lower troposphere and transport in the free troposphere. The Geostationary Interferometric Infrared Sounder (GIIRS) onboard China's FengYun‐4 satellite series is the world's first geostationary hyperspectral infrared sounder. Using observations from FY‐4B/GIIRS, this study presents the first retrieval of HCOOH from a geostationary satellite instrument that captures the HCOOH variation in Asia driven by biomass burning emissions and possible biogenic sources, providing key observations for understanding the complex processes of HCOOH production, evolution, and loss in the atmosphere. This study is an important first step toward monitoring VOCs from geostationary infrared sounders. Key Points: First retrieval of atmospheric HCOOH from a geostationary sounder is demonstratedHCOOH in fire plumes can be continuously tracked with FY‐4B/GIIRSFY‐4B/GIIRS HCOOH observations have comparable sensitivity to IASI [ABSTRACT FROM AUTHOR]

The metal doping is an effective strategy to adjust catalytic performance for indium oxide catalyst in CO2 hydrogenation. In current work, a series dopant, Co, Fe, Ni, Pd, Pt, Rh, and Ru, are selected and examined in CO2 hydrogenation to formic acid by DFT based microkinetic simulation. It is found that substitutional doping is local effect, which mainly promotes the reactivity of adjacent oxygen atoms. The calculations of both CO2 adsorption and hydrogen molecule dissociation certify the positive effects induced by doping, and the adsorption energy of CO2 has a linear relation with the transferred charges for all investigated catalysts which helps to explain the C─O bond activation mechanism. Two pathways, formate and carboxyl, are investigated under same footing. It is noted that doping significantly reduces the hydrogenation barriers on two pathways compared with undoped surfaces. Moreover, the calculated TOF of formic acid formation is greatly increased on doped surfaces and Pt, Pd, and Ru are identified as the most active dopants. In the end, it is concluded that reaction obeys carboxyl mechanism and a valid descriptor of trans‐HCOOH* and H* formation energy is proposed for the screening of effective dopants. [ABSTRACT FROM AUTHOR]

Acidic CO2 electrolysis, enhanced by the introduction of alkali cations, presents a strategic approach for improving carbon efficiency compared to processes conducted in neutral and alkaline environments. However, a significant challenge arises from the dissolution of both organic acids and alkali cations in a strongly acidic feed stream, resulting in a considerable energy penalty for downstream separation. In this study, we investigate the feasibility of using flow-electrode capacitive deionization (FCDI) technology to separate organic acids and recover alkali cations from a strongly acidic feed stream (pH ~ 1). We show that organic acids, such as formic acid and acetic acid, are retained in molecular form in the separation chamber, achieving a rejection rate of over 90% under all conditions. Alkali cations, such as K+ and Cs+, migrate to the cathode chamber in ionic form, with their removal and recovery significantly influenced by their concentration and the pH of the feed stream, but responding differently to the types and concentrations of organic acids. The energy consumption for the removal and recovery of K+ is 4 to 8 times higher than for Cs+, and the charge efficiency is significantly influenced by the types of organic acid products and alkali cations. We conduct a series of electrochemical measurements and analyze the impedance spectroscopy, identifying that hindered mass transfer governed the electrode process. Our findings underscore the potential of FCDI as an advanced downstream separation technology for acidic electrocatalysis processes. [ABSTRACT FROM AUTHOR]

Formic acid is considered a promising hydrogen carrier. Biomass‐derived formic acid can be obtained by oxidative decomposition of sugars. This study explored the production of formic acid from cellobiose, a disaccharide consisting of d‐glucose linked by β‐glycosidic bonds using heterogeneous catalysts under mild reaction conditions. The use of alkaline earth metal oxide solid base catalysts like CaO and MgO in the presence of hydrogen peroxide could afford formic acid from cellobiose at 343 K. While CaO gave 14 % yield of formic acid, the oxide itself was converted to a harmful metal peroxide, CaO2 after the reaction. In contrast, MgO could produce formic acid without the formation of the metal peroxide. The difficulty in selectively synthesizing formic acid from cellobiose using these solid base catalysts was due to the poor conversion of cellobiose to glucose. Using a combination of solid acid and base catalysts, a high formic acid yield of 33 % was obtained under mild reaction conditions due to the quantitative hydrolysis of cellobiose to glucose by a solid acid followed by the selective decomposition of glucose to formic acid by a solid base. [ABSTRACT FROM AUTHOR]

Background: This study developed and validated a simple, robust, and cost-effective RP-HPLC bioanalytical method for the determination of nebivolol hydrochloride (NBH) and amlodipine besylate (AMB) in human plasma. Briefly, NBH and AMB were extracted from plasma through protein precipitation using 5% formic acid and acetonitrile. Chromatographic separation was achieved using an Inertsil ODS-3 V column (150 mm × 4.6 mm, 5 μm) with a mobile phase composed of acetonitrile and buffer (40:60, v/v). The analysis was conducted using UV detection at 215 nm. Results: The bioanalytical method demonstrated linearity for NBH (4.50–180.12 μg/mL) and AMB (3.50–140.06 μg/mL). It exhibited good selectivity and sensitivity, with LLOQ responses within ≤ 20% of the analyte signal. Accuracy and precision were within acceptable limits. The extraction recovery from human plasma showed a CV (%) of 1.15% for NBH and 1.35% for AMB, indicating consistent recovery rates. Stability studies on drug-spiked human plasma at LQC and HQC levels confirmed the stability of the drugs under various conditions. Conclusion: The present bioanalytical method successfully quantified NBH and AMB simultaneously in plasma samples. It demonstrated suitability, supported by high recovery rates and low relative standard deviations. With its proven linearity, accuracy, and precision, this technique is well suited for drug identification in plasma samples. [ABSTRACT FROM AUTHOR]

The hydrogenation of CO2 to produce formic acid has garnered increasing interest as a means to address climate change and promote the hydrogen economy. This research investigates the nanocasting technique for the synthesis of ordered mesoporous nitrogen-doped carbon (MNC-An). KIT-6 functioned as the silica template, while aniline served as the nitrogen–carbon precursor. The resultant MNC-An exhibits cubic Ia3D geometry, possesses significant mesoporosity, and has a high nitrogen content, which is essential for stabilizing ruthenium single atoms. The catalyst exhibited a specific activity of 252 mmolFAgcat−1 following a 2 h reaction at 120 °C. Moreover, the catalyst exhibited exceptional relative activity during five recycling experiments while preserving its catalytic efficacy. The atomically dispersed ruthenium and its Ru3+ oxidation state demonstrated perseverance both before and after the treatment. The results indicated that the synthesized catalyst possesses potential for the expedited commercialization of CO2 hydrogenation to produce formic acid. The elevated carbon yield, along with excellent thermal stability, renders it a viable substrate for attaching and stabilizing atomically dispersed ruthenium catalysts. [ABSTRACT FROM AUTHOR]

This study presents the development and validation of environmentally friendly analytical methods for quantifying Abiraterone Acetate (AA) in both its pure form and commercial pharmaceutical formulations. An optimized High-Performance Liquid Chromatography (HPLC) method was developed using an Agilent Extend C18 column (250 mm × 4.6 mm, 5 μm) at 25 °C. The mobile phase consisted of formic acid and ethanol in isocratic mode, with a flow rate of 1.0 mL min−1, and detection was performed at 253 nm. The spectrophotometric method involved a comprehensive evaluation of AA's spectral properties in various solvents, with ultrapure water providing the most suitable spectra for analysis at 253 nm. Both methods were validated according to ICH guidelines, demonstrating selectivity, linearity, accuracy, precision, detection and quantification limits, and robustness, with correlation coefficients exceeding 0.999 across the 5–30 μg mL−1 concentration range. Comparative statistical analysis using Student's t-test and Fisher's F-test showed no significant differences between the two methods. The environmental impact of both methods was assessed using AGREE and GAPI software, confirming their sustainability. These validated methods offer reliable and eco-friendly approaches for the quantitative analysis of AA in tablet formulations, promoting safer and greener laboratory practices in pharmaceutical analysis. [ABSTRACT FROM AUTHOR]

A fast and sample cleanup approach for fluoxetine in human plasma was developed using protein precipitation coupled with LC–MS-MS. Samples were treated with methanol prior to LC–MS-MS analysis. Chromatographic separation was performed on a reverse phase column with an isocratic mobile phase of methanol and 10 mM ammonium formate pH acidified with formic acid (80:20, v/v) at a flow rate of 0.2 mL/min. The run time was 4 min. Mass parameters were optimized to monitor transitions at m/z [M + H]+ 310 > > 148 for fluoxetine and m/z [M + H]+ 315.1 > > 153 for fluoxetine-d5 as an internal standard. The lower limit of quantification and the dynamic range were 0.25 and 0.25–50 ng/mL, respectively. Linearity was good for intra-day and inter-day validations (R2 = 0.999). The matrix effect was acceptable with CV% < 15 and accuracy% < 15. The hemolytic effect was negligible. Fluoxetine was stable in human plasma for 48 h at room temperature (25 °C), for 12 months frozen at −25 °C, for 48 h in an auto-sampler at 6 °C, and for three freeze/thaw cycles. The validated method was applied in a pharmacokinetic study to determine the concentration of fluoxetine in plasma samples. The study provides a fast and simple bioanalytical method for routine analysis and may be particularly useful for bioequivalence studies. The method was successfully applied to a pharmacokinetic study of fixed-dose fluoxetine in nine healthy volunteers. [ABSTRACT FROM AUTHOR]

Nitrosamine‐related impurities (N‐nitrosomethylamino butyric acid [NMBA], N‐nitrosodiethylamine [NDEA], N‐nitrosodiisopropylamine [NDIPA], N‐nitrosomethylphenylamine [NMPA], N‐nitrosodibutylamine [NDBA], N‐nitrosodimethylamine [NDMA], and N‐nitrosoethylisopropylamine [NEIPA]) and 5‐[4'‐(azidomethyl)‐[1,1'‐biphenyl]‐2‐yl]‐2H‐tetrazole (AZBT) formed during the manufacture of sartan medicines have been classified into human mutagens and carcinogens after long‐term treatment. The study developed a simple, economical but highly sensitive procedure for the simultaneous quantification of seven nitrosamines and AZBT impurities in sartan pharmaceuticals. After extraction with methanol (MeOH) 50%, the compounds were analyzed with a reversed‐phase liquid chromatography–tandem mass spectroscopy with atmospheric‐pressure chemical ionization (APCI) mode (APCI[+] for nitrosamines and APCI[−] for AZBT), selected reaction monitoring, C18 column, gradient elution with 0.1% formic acid in water and in MeOH, respectively. The validated procedure obtained high extraction efficiency (>90%), wide linear range (0.2–50.0 ng/mL NMBA, NDEA, NDIPA, NMPA, and NDBA; 0.5–50.0 ng/mL NDMA and NEIPA; 2.0–100 ng/mL AZBT), limit of quantification < 10% of the acceptance level, recovery range of 85%–115% with relative standard deviation < 15% and minimum matrix effects for all impurities. The procedure was applied to test 16 commercial losartan samples. As a result, eight samples contained AZBT within the current regulatory limits, but no nitrosamine impurities were detected in all samples. [ABSTRACT FROM AUTHOR]

The leading type of ionization technique in mass spectrometry analyses is the ionization at atmospheric pressure. The aim of this study was to assess ESI and APCI ionization efficiency of pesticides introduced to the MS source in four organic phases, non‐doped and doped with formic acid and ammonium formate. Ionization efficiency in modified ESI and APCI, applying in‐source sample heating, was also assessed. The study was primarily designed to support non‐chromatography‐based mass spectrometry pesticides analysis by the direct infusion technique. Evaluation of analysis performances such as calibration performances, detectability, and sensitivity should indicate a top solvent‐additive‐source combination, leading to the highest ionization efficiency and lowest analytes detection limits. [ABSTRACT FROM AUTHOR]

Bacterial keratitis (BK) is an infection that causes inflammation of the cornea and, if severe, can result in blindness. Topical fluoroquinolones combined with corticosteroids have been shown to be useful in the treatment of BK. A rapid, selective, and sensitive bioanalytical method for simultaneous quantification of Gatifloxacin (GAT) and Dexamethasone (DEX) has been developed and validated using tandem mass spectrometry (LC–MS/MS). Optimal separation was accomplished in under 5 min using an Agilent Zorbax C18 column (100 mm × 4.6 mm, 3.5 μm). The mobile phase was composed of a blend of 0.2% formic acid in triple distilled water and methanol with a flow rate of 0.65 mL/min in isocratic mode. GAT and DEX were detected in positive electrospray ionization multiple reaction monitoring mode (MRM), and the retention time was found to be at 1.64 and 2.93 min, respectively. The linearity of GAT and DEX was found to be in the range of 1.56–400 ng mL−1 with good precision and accuracy. The method was validated according to USFDA regulatory guidelines. The validated method was effectively utilized for preclinical pharmacokinetic analysis of GAT and DEX in rabbit tear fluid following the topical application of a commercial formulation. [ABSTRACT FROM AUTHOR]

Transfer hydrogenation of N‐heteroarenes was successfully achieved using a water‐soluble half‐sandwich Cp*Ir‐based catalyst containing a uracil‐based bifunctional abnormal NHC ligand, using HCOOH/HCOONa buffer solution as the hydrogen source. Reduction of N‐heteroarenes was shown to be highly pH‐dependent, and an acidic pH = 3.0 was found to be suitable for the best activity. The catalyst showed excellent functional group compatibility and high turnover number (up to 10,400), with catalyst loadings as low as 0.005 mol%. Finally, we demonstrated the catalyst's efficacy and applicability toward reusable and repetitive transfer hydrogenation using liquid/liquid extraction methodology, which underscored the significance of sustainable usage of noble metal catalysts in such transformations. [ABSTRACT FROM AUTHOR]

The toxicologist ascertains drug assumptions in case of paediatric intoxications and death for overdose. The analytical approach consists of initially screening and consequently confirming drug positivity. We developed a toxicological screening method and validated its use comparing the results with a LC–MS/MS analysis. The method identifies 751 drugs and metabolites (704 in positive and 47 in negative mode). Chromatographic separation was achieved eluting mobile phase A (10 mM ammonium formate) and B (0.05% formic acid in methanol) in gradient on Kinetex Phenyl-Hexyl (50 × 4.6 mm, 2.6 μm) with 0.7 mL/min flow rate for 11 min. Multiple Reaction Monitoring (MRM) was adopted as survey scan and, after an Information-Dependent Analysis (IDA) (threshold of 30,000 for positive and 1000 cps for negative mode), the Enhanced Product Ion (scan range: 50–700 amu) was triggered. The MS/MS spectrum generated was compared with one of the libraries for identification. Data processing was optimised through creation of rules. Sample preparation, mainly consisting of deproteinization and enzymatic hydrolysis, was set up for different matrices (blood, urine, vitreous humor, synovial fluid, cadaveric tissues and larvae). Cut-off for most analytes resulted in the lowest concentration tested. When the results from the screening and LC–MS/MS analysis were compared, an optimal percentage of agreement (100%) was assessed for all matrices. Method applicability was evaluated on real paediatric intoxications and forensic cases. In conclusion, we proposed a multi-targeted, fast, sensitive and specific MRM-IDA-EPI screening having an extensive use in different toxicological fields. [ABSTRACT FROM AUTHOR]

The advancements in renewable energy technologies brought about a significant interest in developing formic acid based chemical and electrochemical processes. These include the electroreduction of carbon dioxide to produce formic acid or direct electrooxidation of formic acid to generate electricity in a fuel cell. Considering the neutral to alkaline nature of electrolytes used in many of these processes, formic acid usually exists as a formate species. Unlike oxalate salt, the direct titration to quantify formate molarity using potassium permanganate (KMnO4) is difficult due to the formation of a suspended colored complex, which poses challenges in identifying the endpoint. Herein, we report two simple and efficient methods for formate and formic acid analysis, by back titration (FBT) using oxalate and iodine, respectively. These methods were shown to have an accuracy of more than 97% at a reduced cost when benchmarked against either nuclear magnetic resonance (NMR) spectroscopy or ion chromatography (IC). The effect of the analyte medium and optimization of the analytical procedure were also investigated. The formate quantification was found to vary insignificantly when different media, such as water, potassium hydroxide, potassium bicarbonate, or potassium sulfate, were used. This signifies the robustness and broader applicability of the FBT methods. Regarding the analytical steps, selecting the appropriate temperature, time, and molar ratio of participating species allowed the quantification of formate or formic acid with accuracy and precision. The analytical methods thus developed can provide alternative, cost-effective solutions for determining formate concentration for the research and development sector and for on-site analysis in industrial settings, where maintaining NMR and IC equipment may not be feasible. [ABSTRACT FROM AUTHOR]

Formic acid is reported to act as a food preservative and feed additive, but its effects on controlling postharvest physiological deterioration (PPD) development in cassava are unclear. In this study, we assessed the effectiveness of different concentrations of formic acid in attenuating PPD occurrence in fresh-cut cassava. The results showed that the concentration of 0.1% (v/v) formic acid could significantly delay the occurrence of PPD, and that the higher the concentration of formic acid supplied, the later the occurrence of PPD symptoms. The physiological and biochemical analysis of 0.5%-formic-acid-treated cassava slices revealed that formic acid decreased the degradation of starch, inhibited the accumulation of hydrogen peroxide (H2O2), malondialdehyde (MDA), and water-soluble pectin in cassava slices with PPD development, and increased the activities of the antioxidant enzymes ascorbate peroxidase (APX) and glutathione reductase (GR). A microscopic observation showed that the formic acid treatment inhibited the enlargement of the intercellular space during the cassava PPD process, which suggests that the formation of an intercellular layer of the cell wall was inhibited by formic acid. This study thus revealed the mechanism used by formic acid to extend the cassava shelf life; however, a detailed evaluation of the possible side effects on, for example, the cyanide content will be needed to categorically ensure the safety of this method. [ABSTRACT FROM AUTHOR]

Biomass from willow and poplar harvested for feed during the growing season may be preserved by ensiling; however, little research has focused on ensiling of these biomasses. This study focuses on the use of ensiling additives to reduce the pH to around 4.0 to secure stable storage. Lab-scale ensiling experiments were conducted with different willow and poplar clones, shoot ages, and harvest times (June or September). Ensiling without additives often resulted in limited pH reduction. The pH could be reduced in the biomass of both species by adding formic acid, and the required dose to reduce the pH to 4.0 (buffering capacity, BC) ranged significantly between biomass types but was in the range of 2–5 kg formic acid (78%) per ton fresh weight. BC decreased with increasing dry matter (DM) content and decreasing crude protein content. The pH could also be reduced during ensiling by applying molasses and/or lactic acid bacteria, although not sufficiently in poplar. Willow biomass was ensiled effectively at the pilot scale with less than 7% DM loss by adding formic acid or by mixing with grass biomass. Comparable pH results were obtained at the lab scale and pilot scale. The study demonstrates how willow and poplar can be ensiled; however, more research is needed on quality changes during ensiling. [ABSTRACT FROM AUTHOR]

Formic acid (FA) is a potential biomass resource of syngas with contents of carbon monoxide (CO, 60 wt.%) and hydrogen (H2, 4.4 wt.%). Among the technologies for FA conversion, the photoreforming of FA has received widespread attention due to its use of green solar energy conversion technology and mild reaction conditions. Herein, a V–W bimetallic solid solution, VxW1−xN1.5 with efficient co-catalytic properties was first and facilely synthesized. When CdS was used as a photocatalyst, the activity performance of the V0.1W0.9N1.5 system was over 60% higher than that of the W2N3 system. The computational simulations and experiments showed the V0.1W0.9N1.5 had great metallic features and large work functions, contributing a faster photo-generated carrier transfer and less recombination, finally facilitating a great performance in cocatalyst for syngas production in photoreforming FA. This work provides an approach to synthesizing novel transition metal nitrides for photocatalysis. [ABSTRACT FROM AUTHOR]

Lilium lancifolium Thunb. is a herbal medicine that is widely used to treat inflammation and lung diseases. In this study, a simultaneous quantitative method was developed for the quality control of BLL using high-performance liquid chromatography coupled with a photodiode array detector (HPLC–PDA), and their antioxidant effects were evaluated. Eight regalosides (i.e., regaloside A, B, C, E, F, H, I, and K) were selected as marker substances and separated on a Gemini C18 reversed-phase analytical column by gradient elution with distilled water–acetonitrile mobile phase containing 0.1% (v/v) formic acid. The method was validated with respect to linearity, sensitivities (limit of detection (LOD) and limit of quantitation (LOQ)), accuracy, and precision. The antioxidant effects of the extract and each component were evaluated using the 2,2-diphenyl-1-picrylhydrazyl radical scavenging assay and 2-2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) assay. The coefficients of determination values used as indicators of linearity for all components were ≥0.9999. LOD and LOQ concentrations were 0.10–0.66 μg/mL and 0.29–2.01 μg/mL, respectively. The recovery was 95.39–103.925% (relative standard deviation; RSD ≤ 2.55%), and precision RSD was <2.78%. The HPLC–PDA method was applied to real samples, and all components were detected at 1.12–29.76 mg/freeze-dried g. The evaluation of antioxidant effects showed that regalosides C, E, and K exhibited significant antioxidant effects. Our knowledge will be appropriately utilized in raw material management and conducting clinical and non-clinical studies on L. lancifolium or herbal medicine prescriptions containing L. lancifolium. [ABSTRACT FROM AUTHOR]

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Industrial CO2 electrolysis via electrochemical CO2 reduction has achieved progress in alkaline solutions, while the same reaction in acidic solution remains challenging because of severe hydrogen evolution side reactions, acid corrosion, and low target product selectivity. Herein, an industrial acidic CO2 electrolysis to pure HCOOH system is realized in a proton-exchange-membrane electrolyzer using an acid-tolerant Bi-based metal-organic framework guided by a Pourbaix diagram. Significantly, the Faradaic efficiency of HCOOH synthesis reaches 95.10% at a large current density of 400 mA/cm2 with a high CO2 single-pass conversion efficiency of 64.91%. Moreover, the proton-exchange-membrane device also achieves an industrial-level current density of 250 mA/cm2 under a relatively low voltage of 3.5 V for up to 100 h with a Faradaic efficiency of 93.5% for HCOOH production, which corresponds to an energy consumption of 200.65 kWh/kmol, production rate of 12.1 mmol/m2/s, and an energy conversion efficiency of 38.2%. These results will greatly aid the contemporary research moving toward commercial implementation and success of CO2 electrolysis technology. This work develops an industrial-level CO2 electrolysis system for formic acid production by constructing a proton exchange membrane electrolyzer with an acid-tolerant Bismuth metal-organic framework. [ABSTRACT FROM AUTHOR]

Transforming carbon dioxide (CO2) into value-added chemicals is an innovative approach to tackling environmental issues and reducing greenhouse impacts. Owing to the excellent synergistic interaction between substrates and dopants, single-atom alloys (SAAs) exhibit promising catalytic performance in converting CO2 into valuable chemicals. In this theoretical investigation, we employed DFT to explore the catalytic potential of single-atom-doped Cu(111) surfaces in the conversion of CO2 to formic acid (HCOOH). Our investigation provides an in-depth analysis of the catalytic properties of Pd/Cu(111) and Pt/Cu(111) surfaces in relation to the Cu(111) surface. We have identified that *CO2 hydrogenation to *HCOO is the rate-determining step. This step exhibits greater kinetic feasibility on the Pd/Cu(111) surface than on the Pt/Cu(111) surface. The electronic state analysis reveals that the single atoms doped in the Cu(111) surface modify the local chemical environment at the nanoscale. The microkinetic simulation results indicate that Pd/Cu(111) achieves the highest turnover frequency (TOF), with a value of 3.78 × 10–5 s–1·site–1 at 500 K and 30 bar, identifying it as a promising catalyst for CO2 hydrogenation. Additionally, our findings suggest that adjusting temperatures at a constant pressure can lead to stabilization of the TOF values on Pd/Cu(111). This work contributes valuable insights for screening effective SAAs in CO2 hydrogenation to HCOOH, offering a promising direction for the development of catalyst design for HCOOH production. [ABSTRACT FROM AUTHOR]

Glycerol oxidation‐assisted water electrolysis has emerged as a cost‐effective way of co‐producing green hydrogen and HCOOH. Still, preparing highly selective and stable nickel‐based metal electrocatalysts remains a challenge. Herein, heterostructure Ni3N/WO3 nanosheet arrays of bifunctional catalysts with large specific surface areas loaded on nickel foam (denoted as Ni3N/WO3/NF) were synthesized. This catalyst was for glycerol oxidation reaction (GOR) and hydrogen evolution reaction (HER) with excellent catalytic performance, a voltage saving of 267 mV compared to oxygen evolution reaction (OER), and a HER overpotential of 104 mV at 100 mA cm−2. The cell voltage in the assembled GOR//HER hybrid electrolysis system reaches 100 mA cm−2 at 1.50 V, 296 mV lower than the potential required for overall water splitting. This work demonstrates that replacing GOR with OER using a cost‐effective and highly active Ni‐based bifunctional electrocatalyst can make hybrid water electrolysis an energy‐efficient, sustainable, and green strategy for hydrogen production. [ABSTRACT FROM AUTHOR]

The deep eutectic solvent (DES) has emerged in recent years as a valuable medium for converting CO2 into valuable chemicals because of its easy availability, stability, and safety, and its capability to dissolve carbon dioxide. CO2 valorization in DES has evolved rapidly over the past 20 years. As well as being used as solvents for acid/base‐promoted CO2 conversion for the production of cyclic carbonates and carbamates, DESs can be used as reaction media for electrochemical CO2 reduction for formic acid and CO. Among these products, cyclic carbonates can be used as solvents and electrolytes, carbamate derivatives include the core structure of many herbicides and pesticides, and formic acid and carbon monoxide, the C1 electrochemical products, are essential raw materials in the chemical industries. An overview of the application of DESs for CO2 valorization in recent years is presented in this review, followed by a compilation and comparison of product types and reaction mechanisms within the different types of DESs, and an outlook on how CO2 valorization will be developed in the future. [ABSTRACT FROM AUTHOR]

Different forms of HCOOH in the depolymerization system play an important role in governing the monomeric products from lignin. We reported two strategies for the introduction of HCOOH to enrich the monophenols from kraft lignin by microwave‐assisted depolymerization. The reaction of lignin models showed that HCOOH was in favor of the cleavage of C−O bonds (β‐O‐4 typically) and partial C−C bonds (Cα−Cβ). Subsequently, Microwave‐assisted depolymerization of lignin with two strategies was conducted via a designed dynamic vapor flow reaction system. Strategy A with HCOOH as pretreatment solvent showed excellent monophenols enrichment with total mass yields of 193.71 mg/g (lignin basis). Strategy B using HCOOH as reforming solvent vapor significantly increased the monophenols selectivity. It presented unique reforming and upgrading performance by generating catechol (42.59 mg/g, lignin basis) and homovanillic acid (17.58 mg/g, lignin basis). This study provided potential strategies for the efficient conversion of kraft lignin into high‐value platform chemicals. [ABSTRACT FROM AUTHOR]

Methanol is being activelPTy investigated as a promising C1 reagent to replace conventional C1 reagents in organic synthesis, due to its properties of being economical, abundant, nontoxic and sustainably producible. However, because of the high enthalpy of dehydrogenation, it has not been reported frequently. Herein, we report that Pt single atoms (Pt1) and Pt clusters (Ptn) are cooperatively loaded on α-MoC to achieve the conversion of various of unsaturated N-containing compounds into value-added N-methylation compounds simply in methanol aqueous solution, successfully avoiding the use of external hydrogen or any additives. The synergy between coexisting Pt1 and Ptn on Pt1+n/α-MoC is identified as necessary to realize the tandem conversion with superior activity and selectivity. Pt1/α-MoC is the active site for in situ hydrogen production from aqueous phase methanol reforming, and Ptn/α-MoC is responsible for the successive hydrogenation and methylation. The partially positive Ptnδ+ species are crucial for the reductive N-methylation reaction, as the strong coordination of N-containing compounds to Pt particles (Ptn) significantly inhibits the catalytic activity. Experimental and DFT results further show that, unlike the traditional hydrogen-borrowing mechanism of methanol via the intermediate formaldehyde, formic acid is found to be a potent intermediate and agent for N-methylation. [ABSTRACT FROM AUTHOR]

The rational design of the electronic structure and elemental compositions of anode electrocatalysts for formic acid electrooxidation reaction (FAOR) is paramount for realizing high‐performance direct formic acid fuel cells. Herein, palladium‐boride nanoflowers (Pd‐B NFs) with controllable boron content are rationally designed via a simple wet chemical reduction method, utilizing PdII‐dimethylglyoxime as precursor and NaBH4 as both reductant and boron source. The boron content of Pd‐B NFs can be regulated through manipulation of reaction time, accompanying with the crystal phase transition from face‐centered cubic to hexagonal close‐packed within the parent Pd lattice. The obtained Pd‐B NFs exhibit increased FAOR mass and specific activity with increasing boron content, showcasing remarkable inherent stability and anti‐poisoning capability compare to commercial Pd and platinum (Pt) nanocrystals. Notably, the sample reacted for 12 h reveals high FAOR specific activity (31.5 A m−2), which is approximately two times higher than the commercial Pd nanocrystals. Density functional theory calculations disclose that the d‐sp orbital hybridization between Pd and B modifies surface d‐band properties of Pd, thereby optimizing the adsorption of key intermediates and facilitating FAOR kinetics on the Pd surface. This study paves the way toward the utilization of metal boride‐based materials with simple synthesis methods for various electrocatalysis applications. [ABSTRACT FROM AUTHOR]

The unique characteristic of 2D transition‐metal dichalcogenide (TMD) semiconductor materials such as PdSe2 is the ability of the bandgap to vary on the basis of the number of layers present. This variation results in a broad bandgap range spanning from semi‐metallic to semiconducting materials, underscoring the significance of precisely controlling the material thickness. In this study, the thicknesses of chemical vapor deposited PdSe2 films are precisely controlled layer‐by‐layer via cyclic atomic layer etching (ALE), which comprised a radical adsorption step generated by oxygen and chlorine plasmas, followed by a desorption step with an organic solvent vapor such as formic acid. Cyclic etching with one monolayer of PdSe2/cycle is achieved using both types of adsorption gases while maintaining the ratio of Se/Pd underlying PdSe2 at ≈2. This cyclic ALE method is also applicable for smoothing TMD material surfaces by isotropically removing individual rough surface layers. Because this etching method only utilizes chemical reactions with radicals generated by plasmas and organic vapors, it is not only unaffected by the physical damage caused by the irradiation of energetic particles such as ions in plasmas, but also is applicable to 3D structure processing. [ABSTRACT FROM AUTHOR]

The development of hydrogen technologies is at the heart of a green economy. As prerequisite for implementation of hydrogen storage, active and stable catalysts for (de)hydrogenation reactions are needed. So far, the use of precious metals associated with expensive costs dominates in this area. Herein, we present a new class of lower-cost Co-based catalysts (Co-SAs/NPs@NC) in which highly distributed single-metal sites are synergistically combined with small defined nanoparticles allowing efficient formic acid dehydrogenation. The optimal material with atomically dispersed CoN2C2 units and encapsulated 7-8 nm nanoparticles achieves an excellent gas yield of 1403.8 mL·g−1·h−1 using propylene carbonate as solvent, with no activity loss after 5 cycles, which is 15 times higher than that of the commercial Pd/C. In situ analytic experiments show that Co-SAs/NPs@NC enhances the adsorption and activation of the key intermediate monodentate HCOO*, thereby facilitating the following C-H bond breaking, compared to related single metal atom and nanoparticle catalysts. Theoretical calculations show that the integration of cobalt nanoparticles elevates the d-band center of the Co single atoms as the active center, which consequently enhances the coupling of the carbonyl O of the HCOO* intermediate to the Co centers, thereby lowering the energy barrier. The area of catalytic dehydrogenation is largely dominated using precious metals. Here the authors introduce a new class of more affordable Co-based catalysts, where highly dispersed single-metal sites work synergistically with small, well-defined nanoparticles to enable efficient formic acid dehydrogenation [ABSTRACT FROM AUTHOR]

Hydrogen spillover in metal‐supported catalysts can largely enhance electrocatalytic hydrogenation performance and reduce energy consumption. However, its fundamental mechanism, especially at the metal–metal interface, remains further explored, impeding relevant catalyst design. Here, we theoretically profile that a large free energy difference in hydrogen adsorption on two different metals (|ΔGH‐metal(i)−ΔGH‐metal(ii)|) induces a high kinetic barrier to hydrogen spillover between the metals. Minimizing the difference in their d‐band centers (Δϵd) should reduce |ΔGH‐metal(i)−ΔGH‐metal(ii)|, lowering the kinetic barrier to hydrogen spillover for improved electrocatalytic hydrogenation. We demonstrated this concept using copper‐supported ruthenium–platinum alloys with the smallest Δϵd, which delivered record high electrocatalytic nitrate hydrogenation performance, with ammonia production rate of 3.45±0.12 mmol h−1 cm−2 and Faraday efficiency of 99.8±0.2 %, at low energy consumption of 21.4 kWh kgamm−1. Using these catalysts, we further achieve continuous ammonia and formic acid production with a record high‐profit space. [ABSTRACT FROM AUTHOR]