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The article focuses on recent advancements in chemistry, highlighting the development of new materials and chemical processes. Topics include the synthesis of insensitive energetic materials with enhanced detonation performance, the use of vanadium(V) complexes for syndiospecific ring-opening metathesis polymerization (ROMP) of cyclic olefins, and the exploration of metal-support interactions to enhance catalytic activity for hydrogen production.

The synthesis of noble metal/TiO2 composites without the use of additional reducing agents or surfactants is a notable achievement in catalyst preparation, as it simplifies the process and reduces potential impurities. A detailed analysis of catalysts using a range of methods like XRD, TEM, XPS, BET, and FT-IR offers a comprehensive insight into their structural and surface characteristics, essential for understanding their catalytic performance. The observation of enhanced catalytic activity with Pt-loaded composite catalysts compared to Pd and Au-loaded counterparts highlights the importance of noble metal selection in catalytic applications. Through BET and TEM characterization, it can be observed that there is no significant difference between the specific surface area of all noble metal/TiO2 composites and the size of the noble metal, which ranges from 2–7 nm. The correlation between the catalytic efficiency and the metal work function, along with the insights from XPS analysis, underscores the significance of the metal–titanium dioxide interaction in determining catalytic efficiency. This interaction may involve tuning the surface's electronic structure, the chemical bonding between the metal and the carrier, and the formation of surface active sites. These sites can adsorb reactants and facilitate the reaction, thus improving the catalytic activity and selectivity. This study provides an in-depth understanding and an important reference for the design and optimization of catalysts for hydrogen production from formic acid, which can help promote progress and applications in related fields. [ABSTRACT FROM AUTHOR]

Electrochemical carbon dioxide reduction reaction (ECO2RR) is an effective means to promote carbon cycling. Recently, Bi-based metal–organic frameworks (MOFs) have attracted significant attention due to their high efficiency for formic acid generation in ECO2RR, however, their composition and morphology transformation during electrocatalysis still lack a deep exploration. Herein, a Bi-MOF with 2,4,6-tris(4-carboxyphenyl)-1,3,5-triazine (H3TATB) ligand is used as the prototype to investigate its in situ transformation during ECO2RR. With various characterization methods, the detailed transformation processes are revealed. Firstly, the Bi-MOF was transformed into Bi2O2CO3 due to ligand substitution in KHCO3 electrolyte, resulting in changes in both shape and composition. Secondly, during ECO2RR, the Bi3+ ions can be reduced into metallic Bi0 nanoparticles and act as the real active component for ECO2RR. The resultant catalyst exhibits a high selectivity of up to 94.3% towards formate generation. At an optimal potential of −1.08 V vs. RHE, the catalyst can maintain a current density of −25 mA cm−2 and a faradaic efficiency of formate over 90% for 14.5 hours. This work not only develops an efficient electrocatalyst for ECO2RR but also provides a new insight into the in situ reconstruction of MOF precursor into the active catalyst, which is useful for the design and synthesis of other materials. [ABSTRACT FROM AUTHOR]

A number of phosphomolybdic acid dispersed on SBA-15 catalysts with structural defects and strong acidity were synthesized and applied for the production of ultralow sulfur diesel. The oxygen defect concentration in the catalysts was quantitatively determined by the Rietveld refinement method. These catalysts contained many Brønsted (B) and Lewis (L) acid sites (648 to 1479 μmol g−1) depending on the heteropolyacid content and the thermal treatment. The Mo5+/Mo6+ ratio calculated by XPS technique varied from 0.21 to 0.27%, indicating the creation of oxygen defects in the Keggin unit. The area under the IR absorption band at 980 cm−1 (characteristic of the Mo＝O bond) in the FTIR spectra of different catalysts was found to be inversely proportional to the variation of L acidity as a function of temperature, indicating that oxygen defects are the origin of the L acidity. In the oxidation reaction for removing dibenzothiophene, DBT, from a model diesel, the DBT conversion correlated well with the oxygen defect concentration and total surface acidity, confirming that the surface acidity and oxygen defects played key roles in DBT adsorption and oxidation. Almost 100% DBT conversion was achieved on the best 30 wt% H3PMo12O40/SBA-15 catalyst under the optimal reaction conditions (reaction time 60 min, reaction temperature 70 °C, H2O2/DBT molar ratio 6–8, catalyst concentration 2–2.5 mg ml−1, and hydrogen peroxide to formic acid molar ratio 1.5). A novel mechanism of the DBT oxidative removal in a biphasic system involving the participation of the neighboring L and B acid sites, oxygen defects, and the formation of peroxometallic and superoxometallic species was proposed. [ABSTRACT FROM AUTHOR]

The strategies for optimizing the morphology/structure and regulating the active sites of materials are effective ways to improve their electrocatalytic performance in the hydrogen evolution reaction (HER) and electrooxidation reaction. Herein, we demonstrate a facile strategy for constructing a NiO/NiCo2O4 porous nanowire catalyst on nickel foam (NiO/NiCo2O4/NF) as a bifunctional electrocatalyst to enhance the electrocatalytic performance for coupling the HER with the glucose oxidation reaction (GOR). Benefiting from the unique 1D porous nanowire structure and enhanced interfacial synergistic effect of the bicomponent catalyst, optimized NiO/NiCo2O4/NF-300 exhibited remarkable electrocatalytic activities for the GOR and HER with low potentials of 1.128 V and 0.212 V, respectively, at 100 mA cm−2. Moreover, the GOR exhibited a high yield of 72% for formic acid. This study provides a promising and simple strategy for the construction of 1D NiO/NiCo2O4 porous nanowire electrocatalysts with rich heterogeneous interfaces and paves a facile pathway for accelerating biomass electrochemical reaction-assisted hydrogen production. [ABSTRACT FROM AUTHOR]

The electrocatalytic oxidation of carbon-based liquid fuels, such as formic acid and alcohols, has important applications for our renewable energy transition. Molecular electrocatalysts based on transition metal complexes provide the opportunity to explore the interplay between precise catalyst design and electrocatalytic activity. Recent advances have seen the development of first-row transition metal electrocatalysts for these transformations that operate via hydride transfer between the substrate and catalyst. In this Frontier article, we present the key contributions to this field and discuss the proposed mechanisms for each case. These studies also reveal the remaining challenges for formate and alcohol oxidation with first-row transition metal systems, for which we provide perspectives on future directions for next-generation electrocatalyst design. [ABSTRACT FROM AUTHOR]

Carbon dioxide reduction together with aerobic oxidative cyclization using eosin Y-based light-harvesting photocatalysts remains a key challenge. In this study, we present the first-ever synthesis of unique in situ Se-infused eosin Y (Sein–EY) flexible photocatalysts through a simple one-pot method. The as-synthesized Sein–EY flexible film photocatalyst exhibits outstanding performance for the production of formic acid (204 μM in 2 h) and aerobic oxidative cyclization of thioamides via the formation of C–N/C–S bonds with outstanding yields (98.6%) when exposed to solar light. The presence of infused Se significantly extends the solar light absorption capacity of the Sein–EY photocatalyst, reaching up to 580 nm. This study opens up a new pathway for the rational design and synthesis of potentially effective Se-infused-EY photocatalysts through a simple and scalable method, enabling both solar chemical production and efficient one-pot three-component reactions. [ABSTRACT FROM AUTHOR]

The synthesis of deuterated gem-difluoroalkenes via selective deuterodefluorination of β-CF3-cinnamates using a nickel catalyst has been reported for the first time. Commercially available deuterated formic acid is a cheap and convenient deuterium source. The nickel-catalyst showed high selectivity for monodefluorination and avoided competitive reactions such as multiple defluorination or hydrogenation. [ABSTRACT FROM AUTHOR]

We present a novel deoxygenation method for heterocyclic Noxides utilizing iodide as a catalyst. Iodide acts as a reducing catalyst that is regenerated by formic acid, which also serves as a Brønsted activator and solvent. The method demonstrates high efficiency and excellent selectivity in the reduction of a variety of heterocyclic N-oxides and tertiary amines. Our computational DFT investigation revealed that the reduction mechanism entails a direct interaction between iodide and the oxygen of the N-oxide within a Mg2+/formic acid framework, resulting in the formation of the N-heterocycle and the release of a hypoiodite unit. Additionally, a molecular mechanism for the regeneration of iodide from hypoiodite, facilitated by formic acid, is suggested. This method provides an environmentally friendly approach for the deoxygenation of N-oxides and related species. [ABSTRACT FROM AUTHOR]

Formic acid is used as a green carrier for hydrogen storage and production. Here, in order to achieve rapid dehydrogenation of formic acid, the catalyst PdNi/OPDA-MWCNTs is synthesized by reducing bimetallic PdNi nanoparticles on o-phenylenediamine (OPDA) modified multi-walled carbon nanotubes (MWCNTs). Ultrafine metal nanoparticles with a size of 2.6 nm are obtained in the presence of amine groups. The catalyst system Pd0.7Ni0.3/OPDA-MWCNTs catalyzes hydrogen production from formic acid in an additive-free environment with excellent activity, reaching the turnover frequency (TOF) value of 1303 h−1 at 323 K. This is comparable to most reported values. In addition, the catalyst maintains good catalytic activity in five-cycle tests under the same conditions. [ABSTRACT FROM AUTHOR]

This study introduces a novel catalyst designated as 2.6% Co/MXene, comprising cobalt (Co) nanoparticles supported by MXene. The synthesis of the 2.6% Co/MXene catalyst involved direct pyrolysis of a composite material, composed of a Co/Zn bimetal metal–organic framework and MXene. Catalytic transfer hydrogenation of functionalized nitro compounds into the corresponding formamides employed formic acid as both the hydrogen donor and formylation agent, demonstrating remarkable activity and selectivity. Control experiments validated that Co nanoparticles served as the active sites for reductive transformation. Systematic characterization and comprehensive experiments have confirmed that the superior catalytic performance of the 2.6% Co/MXene catalyst can be attributed to the uniform distribution of Co nanoparticles, a high density of basic sites, and the 3D porous architecture of the MXene support. Furthermore, the 2.6% Co/MXene catalyst exhibited excellent recyclability, preserving its catalytic activity and selectivity across four consecutive cycles. [ABSTRACT FROM AUTHOR]

The document is a contents list for the New Journal of Chemistry, providing a range of research topics for library patrons interested in chemistry. It includes articles on the transformation of CO2, mechanochromic photoluminescence, nanocellulose-based electrocatalysts, bone formation rate prediction, and the synthesis of halogenated benzimidazolyl-C nucleosides. The journal also covers industrial chemistry, material innovations, and interdisciplinary features. Additionally, the document includes a retraction notice for a previous paper. [Extracted from the article]

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]

MoP nanofiber-coupled Pd nanoparticles were demonstrated as efficient catalysts for formic acid-assisted water splitting in hydrogen generation. The theoretical calculations indicated that the OH on the surface of MoP through d–p bonding promoted the oxidation of CO at the Pd sites, and improved the ability to resist CO poisoning. As a result, enhanced catalytic performance was indicated. [ABSTRACT FROM AUTHOR]

Although CO2 hydrogenation to formic acid has been widely investigated, the design of highly stable and effective heterogeneous catalysts is a long-standing challenge due to the instability of the active intermediate in water. Herein, both theoretical and experimental results revealed that the active Ir-H species appearing in the CO2 hydrogenation process can be easily hydrolyzed, resulting in the deactivation of the catalyst. Further research constructed a strategy to protect the active Ir-H species by utilizing a directlyknitted PNP-based catalyst (p-PNP-Ir) for CO2 hydrogenation to formic acid. An unpredictable conversion (TON = 1.11 × 106) can be achieved using p-PNP-Ir in water, being 3.15 times higher than that using the monomer PNP-Ir. Besides, the solid catalysts can be easily recycled for at least 15 runs without activity loss, highlighting their potential for practical applications in industry. [ABSTRACT FROM AUTHOR]

The utilization of lignin in material fabrication has garnered significant attention despite its complex structure that greatly limits its applications. This study reports a green method for grading and modifying lignin to prepare stable hydrophobic coatings via the solvent/anti-solvent (ethanol/water) self-assembly method. First, the formic acid lignin particle (FLP) is prepared and the underlying mechanism is primarily ascribed to the hydrogen bonding, π–π interactions among aromatic groups within and between molecules, and hydrophobic interactions. The lignin nanoparticles were utilized to chelate with metal ions (iron) in order to obtain the stable hydrophobic coatings using the special nanostructures of FLP. This hydrophobic coating could be applied to different substrates (blocks, straw, and fabric). The cotton fabric exhibited an initial water contact angle (WCA) that increased from 73.4° to 129.6°, and excellent chemical and physical hydrophobic performance. Moreover, this coating has strong self-cleaning ability and could be used for oil–water separation. In this newly proposed fabrication, ethanol can be recovered in the preparation of lignin nanoparticles, which makes the green and facile preparation of a stable hydrophobic coating possible. Additionally, this work is important in upgrading formic acid lignin by controlling the polarity into value-added hydrophobic materials via green classification. [ABSTRACT FROM AUTHOR]

Solution-Cathode Glow Discharge Optical Emission Spectrometry (SCGD-OES) is a cost-effective analytical technique due to its miniaturization potential and reduced consumption, useful for on-line and in situ aqueous solution elemental analysis, and to its adequate limits of detection, which are, on average, comparable with those of ICP-OES. The elemental response in SCGD-OES is frequently enhanced making use of low molecular weight compound additives, such as formic acid (HCOOH); however, this enhancement was shown to be affected by the presence of significant amounts of Na+ and Cl− ions, which are extensively present in a wide variety of samples. In this context, this work delves into the impact of HCOOH on analyte emission signals when analyzing solutions containing high concentrations of other cations (Na+, K+, Mg2+, and Ca2+) and anions (SO42−, Cl−, NO3−, HCO3− and Br−), which make up an ample variety of sample matrices, on SCGD-OES. In particular, the atomic emission intensity of certain analytes is observed to decline with increasing HCOOH additive concentration under certain sample matrix conditions. This intensity depression mainly appears when the sample matrix contains alkali cations, regardless of the anion type. Interestingly, elements with notable chemical vapor generation (CVG) efficiencies, such as Hg, Ag, Pb and In, maintain the positive HCOOH enhancement of emission intensity. HCOOH addition enhancement is also evaluated in a more complex sample, artificial seawater, showing similar results compared to those obtained with high NaCl concentration solutions due to the high proportion of these ions in seawater. Finally, the analytical performance of SCGD-OES is evaluated in terms of sensitivity and limits of detection, resulting that the addition of HCOOH for seawater analysis pays off when CVG-prone elements are targeted. [ABSTRACT FROM AUTHOR]

In the context of carbon neutrality, the efficient conversion of CO2 is an ideal approach to solving current environmental deterioration and energy shortages. Conversion of CO2 to HCOOH through a photoelectrochemical (PEC) approach is efficient and green. However, achieving efficient PEC reduction of CO2 to HCOOH within a wide potential window remains a challenge. In this work, the photoelectrochemical system was constructed using a CxNy/BiVO4 photoanode and lattice-dislocated Bi (LD-Bi) nanosheets to achieve efficient and stable PEC reduction of CO2 to HCOOH. The PEC tests indicated that the Faraday efficiency of HCOOH (FEHCOOH) of the system was up to 93.8% at a cell voltage of −2.2 V, and FEHCOOH still maintained 85.7% after five cycles of experiments. Under the optimal cell voltage of −2.2 V, the system achieved excellent stability for 10 h. In addition, a series of electrochemical characterization techniques indicated that the improvement of water oxidation performance is conducive to the efficient reduction of CO2 to HCOOH. Based on Bi-based nanomaterials, the work achieves an efficient reduction of CO2 to HCOOH through the synergistic effect of photoanode and cathode, which provides certain ideas for efficient conversion of CO2. [ABSTRACT FROM AUTHOR]

Formic acid (FA) is a bulk chemical and a promising hydrogen energy carrier. The development of FA production from renewable biomass instead of multiple-step production from diminishing fossil resources is attractive. Formaldehyde (FAld) is another bulk chemical but industrial production requires high temperatures (250–600 °C). Herein, efficient oxidation of biomass to FA coupled with low-energy FAld production was developed using heteropoly acids as catalysts. Biomass and derivatives were oxidized to FA in yields of up to 88.6% while methanol was selectively oxidized to FAld at 90–190 °C with a markedly enhanced reaction rate. The synergistic mechanism has been unveiled that biomass activates methanol oxidation by boosting the catalytic redox cycle to form hydroxyl radicals and methanol scavenges the hydroxyl radicals to inhibit the overoxidation of biomass. This work opens up a promising direction for efficient FA production from biomass coupled with low-energy oxidation of alcohols to aldehydes. [ABSTRACT FROM AUTHOR]

Due to the requirement to establish renewable energy sources, formic acid (FA), one of the most probable liquid organic hydrogen carriers (LOHCs), has received great attention. Catalytic formic acid dehydrogenation in an effective and environmentally friendly manner is still a challenge. The N3Q3 ligand (N3Q3 = N,N-bis(quinolin-8-ylmethyl)quinolin-8-amine) and the square pyramidal [Cu(N3Q3)Cl]Cl complex have been synthesised in this work and characterised using several techniques, such as NMR spectroscopy, mass spectrometry, EPR spectroscopy, cyclic voltammetry, X-ray diffraction and DFT calculations. This work investigates the dehydrogenation of formic acid using a molecular and homogeneous catalyst [Cu(N3Q3)Cl]Cl in the presence of HCOONa. The mononuclear copper complex exhibits catalytic activity towards the dehydrogenation of formic acid in H2O with the evolution of a 1 : 1 CO2 and H2 mixture. The activation energy of formic acid dehydrogenation was calculated to be Ea = 86 kJ mol−1, based on experiments carried out at various temperatures. The Gibbs free energy was found to be 82 kJ at 298 K for the decomposition of HCOOH. The DFT studies reveal that [Cu(N3Q3)(HCOO−)]+ undergoes an uphill process of rearrangement followed by decarboxylation to generate [Cu(N3Q3)(H−)]+. The initial uphill step for forming a transition state is the rate-determining step. The [Cu(N3Q3)(H−)]+ follows an activated state in the presence of HCOOH to liberate H2 and generate the [Cu(N3Q3)(OH2)]2+. [ABSTRACT FROM AUTHOR]

Pt/C and SO42−/ZrO2 were mechanically mixed as the catalysts for p-aminophenol synthesis by catalytic transfer hydrogenation of nitrobenzene in water with formic acid as the hydrogen source. The effect of Pt loading and the solid acid on the reaction was investigated. PAP selectivity reached a maximum at a loading of 1 wt%. The characterization results revealed the presence of three valence states of Pt. Pt0 was beneficial for the nitrobenzene hydrogenation, while higher valence Pt contributed to the formic acid decomposition. The catalytic performance of different solid acid catalysts, including HZSM-5, Hβ, SO42−/ZrO2 and SO42−/TiO2, was compared. It was found that Lewis acid sites with strong acid strength were favorable for p-aminophenol formation, and SO42−/ZrO2 showed higher catalytic activity for the reaction. Using Pt/C + SO42−/ZrO2 as the catalyst, the reaction conditions were optimized. Under the optimal reaction conditions, the nitrobenzene conversion and the p-aminophenol selectivity were 80.0% and 47.6%, respectively. The reaction mechanism was also proposed based on the main by-products of the reaction. [ABSTRACT FROM AUTHOR]

In this work, NaH2PO2, Na2S2O3 and CdCl2 were used to synthesize P-doped CdS samples for the photocatalytic decomposition of formic acid to CO reaction. The CO production rates and selectivity of P-doped CdS are as high as 24.5 mmol g−1 h−1 and 92.4%, in which the rate is 7 times higher than that of the pure CdS. Multiple characterizations show that the P-doping increases the specific surface area, widens the band gap and shifts the energy band position of CdS, resulting in enhanced photocatalytic activity. [ABSTRACT FROM AUTHOR]

The default choice of mobile phase acidifier for bottom-up LC-MS proteomic analyses is 0.10% formic acid because of its decent acidity, decent ion pairing ability, and low suppression of electrospray ionization. In recent years, state-of-the-art columns have been designed specifically to provide efficient separation even when using an MS-friendly mobile phase of low ionic strength. Despite this, no attempts have been made to improve the sensitivity of the MS-based analytical methods by reducing the amount of formic acid in the mobile phase. In this study, we evaluated the effect of reduced formic acid concentration in the mobile phase on the chromatographic behavior and MS response of peptides when separated using columns packed with a C18 stationary phase with a positively charged surface. Using 0.01% formic acid in the mobile phase maintained excellent chromatographic performance and increased MS signal response compared to the standard of 0.10%. The enhanced MS response translated to about 50% improved peptide identifications depending on the complexity and amount of sample injected. The increased retention of peptides at a reduced formic acid concentration was directly proportional to the number of acidic residues in the peptide sequence. The study was carried out by covering a spectrum of protein samples with varied complexity using analytical flow, micro-, and nanoflow regimes to expand the applicability in routine practice. [ABSTRACT FROM AUTHOR]

Multistage mass spectrometry experiments, isotope labelling and DFT calculations were used to explore whether selective decarbonylation of formic acid could be mediated by molybdate anions [(MoO3)x(OH)]− (x = 1 and 2) via a formal catalytic cycle involving two steps. In step 1, both molybdate anions undergo gas-phase ion-molecule reactions (IMR) with formic acid to produce the coordinated formates [(MoO3)x(O2CH)]− and H2O. In step 2, both coordinated formates [(MoO3)x(O2CH)]− undergo decarbonylation under collision-induced dissociation (CID) conditions to reform the molybdate anions [(MoO3)x(OH)]− (x = 1 and 2), thus closing a formal catalytic cycle. In the case of [MoO3(O2CH)]− an additional decarboxylation channel also occurs to yield [MoO3(H)]−, which is unreactive towards formic acid. The reaction between [Mo18O3(18OH)]− and formic acid gives rise to [Mo18O3(O2CH)]− highlighting that ligand substitution occurs without 18O/16O exchange between the coordinated 18OH ligand and HC16O2H. The reaction between [(MoO3)x(OD)]− (x = 1 and 2) and DCO2H initially produces [(MoO3)x(OH)]− (x = 1 and 2), indicating that D/H exchange occurs. DFT calculations were carried out to investigate the reaction mechanisms and energetics associated with both steps of the formal catalytic cycle and to better understand the competition between decarbonylation and decarboxylation, which is crucial in developing a selective catalyst. The CO and CO2 loss channels from the monomolybdate anion [MoO3(O2CH)]− have similar barrier heights which is in agreement with experimental results where both fragmentation channels are observed. In contrast, the dimolybdate anion is more selective, since the decarbonylation pathway of [(MoO3)2(O2CH)]− is both kinetically and thermodynamically favoured, which agrees with experimental observations where the CO loss channel is solely observed. [ABSTRACT FROM AUTHOR]

We present a novel green synthetic protocol for the construction of a broad range of substituted fused azabicyclo[3.3.1]nonadiquinoline scaffolds through a formic acid catalyzed formal [4 + 2] annulation/Mannich/dearomatization domino reaction. This unified strategy shows a broad substrate scope with high functional group tolerance, resulting in good to high yields under environmentally benign, transition-metal-free, low-cost, and operationally simple conditions. The current method outperforms existing methods in terms of green and sustainable conditions. The reaction mechanism was confirmed based on DFT calculations. [ABSTRACT FROM AUTHOR]

The rise in demand for biomass as a renewable energy source is being seen as an alternative energy source to conventional fossil fuels. Blending of biodiesels and bioethanol in gasoline is the initial step towards complete utilization of biomass fuels. Glycerol is a byproduct generated in vast quantities during biodiesel production. Glycerol, on further oxidation, can produce several value-added products in conjunction with hydrogen (H2) through photo-/electrocatalysis (PEC/EC). Valuable products from glycerol include 1,3-dihydroxyacetone, glyceraldehyde, tartronic acid, formic acid, and glyceric acid. Glycerol can be used as a feedstock in PEC/EC cells along with water. An intriguing strategy unfolds by combining the oxidation of biomass-derived compounds at the anode with the hydrogen evolution reaction taking place at the cathode, all contained within a biomass electrolysis or photo-reforming reactor. This approach enables the simultaneous production of high-value chemicals and hydrogen, while minimizing energy consumption and reducing CO2 emissions. This review seeks to integrate essential insights into photo- and electro-assisted catalysis, with the objective of offering a holistic comprehension of the overall reaction mechanisms involved in the photo-/electrocatalytic oxidation of glycerol. At the same time, various transition metal-based photo-/electrocatalysts for glycerol valorization are reviewed and discussed in great detail. Moreover, this evaluation carefully examines the obstacles and possibilities for the advancement of photo-/electrocatalytic glycerol oxidation, aligning with future demands for sustainability in the global energy landscape. [ABSTRACT FROM AUTHOR]

We present a convenient and efficient deoxygenation method for synthesizing disulfides and thioethers. The reaction involves an iodide-catalyzed reduction of methyl sulfinates or sulfoxides, respectively, employing formic acid as a stoichiometric reductant. The methodology demonstrates excellent yields and remarkable orthogonality towards other reducible functional groups. In silico explorations revealed the synergistic action of formic acid and in situ generated hydroiodic acid as Brønsted donors within a formic acid framework. This molecular arrangement activates the sulfinyl group and promotes subsequent deoxygenation. Notably, this approach enables the deoxygenation of sulfur-based functional groups using formic acid as the stoichiometric reductant without needing transition metals or strong acidic media such as hydroiodic acid. Overall, this methodology contributes to the advancement of the reduction of diverse oxygenated sulfur-containing compounds in a sustainable approach. [ABSTRACT FROM AUTHOR]

The recent emergence of low-dimensional copper-based halide perovskite Cs3Cu2I5, for use in optoelectronics and radiation detection, has evoked considerable interest. Presently, Cs3Cu2I5 single crystals grown using solution methods barely have clearly defined crystal planes and the crystal quality remains inferior. In this work, we have achieved high-quality Cs3Cu2I5 single crystals featuring prominent crystal habit planes through reducing the growth rate by controlling the concentration of I- ions via the addition of formic acid. The slow reaction between I3- and formic acid at a lower growth temperature can effectively control the concentration of I- ions in the solution, thereby reducing the growth rate and extending the metastable growth range simultaneously. This optimized process can yield high-quality single crystals, with a reduced full width at half maxima (FWHM) of 0.047° for the X-ray rocking curve on the (002) natural crystal habit plane, a substantially improved energy resolution of 7.1% for a photon energy of 511 keV, and an increased absolute light yield to 39 000 photons per MeV. Our study demonstrates that the reaction-controlled growth may be an effective way to improve the crystal quality of the copper-based halide perovskite. [ABSTRACT FROM AUTHOR]

The direct CO2 hydrogenation to formic acid is appealing since it is a potential hydrogen storage material and can be a precursor of higher value-added products. Due to thermodynamic limitations, developing an efficient catalyst system for this process is quite a challenge. Herein, a Ni-based N-modified TiO2-supported catalyst that showed exemplary activity and selectivity toward formic acid synthesis (757 TON), which was reported to be the highest over noble metal-free catalyst system, is designed. The combined impact of Ni and N over TiO2 as a support was thoroughly investigated in this research for improved activity in the selective conversion of CO2 to formic acid. X-ray photoelectron spectroscopy and X-ray absorption spectroscopy investigations showed direct coordination between Ni and N, which emphasizes the metal support interaction for significantly higher catalytic activity. In-depth characterization of Ni/N-TiO2 reveals that CO2 undergoes insertion reaction with H2 to yield formic acid on Ni0 as an active surface via the formate intermediate. Complementary DFT studies elucidate the pivotal effect of nitrogen doping on the TiO2 surface, which provides a more feasible pathway than pure TiO2 by lowering the activation barriers. More significantly, the catalyst demonstrated a steady performance in experiments involving continuous recycling and long-term study. [ABSTRACT FROM AUTHOR]

2,4-Dihydroxybutyric acid (2,4-DHB) is an important fine chemical, which can be used as a precursor in the production of important chemicals. Methanol, as an attractive C1 compound, is an ideal nonfood sugar feedstock for biomanufacturing. In this study, we reported for the first time the biosynthesis of 2,4-DHB in engineered Escherichia coli from a mixture of methanol and glucose. In this process, methanol dehydrogenase was used to convert methanol into formaldehyde, and the key intermediate 2-keto-4-hydroxybutyric acid was synthesized through the condensation of formaldehyde and pyruvate derived from glycolysis by pyruvate-dependent aldolase, which was subsequently transformed into the target product 2,4-DHB by an enzymatic hydrogenation reaction. The new pathway demonstrated the feasibility of producing 2,4-DHB from methanol and glucose in E. coli. For improving the production of 2,4-DHB step by step, dehydrogenases and aldo-keto reductases with higher activity towards 2,4-DHB were screened, and the pyruvate degradation pathway genes were knocked out to enhance the flux from pyruvate towards 2,4-DHB biosynthesis, resulting in the strain DHB9 with about 10-fold improvement compared to the initial strain DHB4. Additionally, the methanol dehydrogenase MDHCn with higher enzymatic activity was obtained by screening. The mutant MDHCn (G48F) with improved activity in vitro was obtained by rational analysis of MDHCn, and the results showed that the enzymatic activity of MDHCn (G48F) increased 3-fold in vitro compared with that of the wild type. Finally, on the basis of the above work, the best engineered strain DHB13 was constructed by knocking out the gene (frmRAB) responsible for the conversion of formaldehyde to formic acid, and the target product 2,4-DHB was accumulated up to 14.6 g L-1 in a 5 L bioreactor. To date, the highest concentration of 2,4-DHB has been achieved in this work, which is promising to make the bioprocess feasible from an economic perspective. Moreover, one glucose molecule and two methanol molecules can be bio-transformed into two 2,4-DHB molecules with 100% conversion of carbon atoms in theory, showing the high carbon atom economy of the novel synthetic metabolic pathway. [ABSTRACT FROM AUTHOR]

We develop a facile, selective edge etching strategy to create edge sites in Pd metallene using acetic acid. The created edge sites remarkably increase the electrochemically active surface area but reduce the charge transfer resistance, resulting in significant enhancement of catalytic activity and stability toward formic acid oxidation. [ABSTRACT FROM AUTHOR]

Photocatalytic oxidation shows great potential in the valorization of biomass under mild conditions, while the selectivity control is particularly challenging for the complex and reactive bio-polyols. Herein, we report a selective photocatalytic process to convert bio-polyols into formic acid (FA) or carbon monoxide (CO) by controlling the phase of TiO2. The bio-polyols are facially oxidized to formic acid (FA) which is stable over rutile and could be dehydrated to CO over anatase TiO2. Through controlling the phase, FA or CO could be obtained from a wide range of bio-polyols with selectivity up to 63% or 52%. Our studies elucidate that the phase-dependent selectivity is essentially derived from the difference in the adsorption configuration of FA. In situ Fourier transform infrared spectroscopy (FTIR) and density functional (DFT) calculations were used to study the FA decomposition process on the surface of TiO2. The phase-dependent FA decomposition is mainly derived from the different surface geometry, which affects the configuration of FA adsorption. Molecular adsorbed FA on anatase favors the dehydration of FA to CO while bidentate dissociated adsorption of FA on the rutile phase is inert to be further converted. This work provides a new horizon to the design of photocatalytic systems for biomass conversion. [ABSTRACT FROM AUTHOR]

In this paper, ultrathin layers of carbon nitride were obtained by dissolving urea in different amounts of water and used as a carrier to prepare catalysts for formic acid dehydrogenation. The catalytic activity of the carbon nitride supported Pd catalyst in formic acid dehydrogenation was investigated. The ratio of urea to water played a key role in the type and content of nitrogen-containing functional groups, and then enhanced the catalytic performance by regulating the electronic properties of Pd. The Pd/CN-U1W5 catalyst exhibited excellent catalytic activity for the production of hydrogen from formic acid with an initial TOF of 1058 h−1 at 348 K. It was found that the high catalytic performance of the catalyst could be attributed to the strong interaction between Pd nanoparticles and pyridinic N, small Pd nanoparticle size and highly dispersed Pd nanoparticles. [ABSTRACT FROM AUTHOR]

A simple, low-cost and sensitive technique using infrared radiation for thermochemical vapor generation coupled with atomic spectrometry was developed for the determination of mercury species in biological matrices. Thermochemical vapor generation (TVG) of inorganic and methylmercury species can be achieved by heating samples of formic acid solubilized materials with and without the use of hydrogen peroxide, respectively, at temperatures of 165 to 285 °C. Power output from a 1000 W infrared lamp was regulated via temperature-controlled output measured with a thermocouple. A quartz tube was used to flow the sample through the TVG reactor. The impacts of formic acid and hydrogen peroxide concentration, temperature and carrier gas flow (N2) were evaluated in the system on response from inorganic and methylmercury in order to identify optimal conditions for thermochemical vapor generation efficiency. The accuracy of the method was validated using Certified Reference Materials NIST 1641d and NRC DORM-1 and DOLT-3. [ABSTRACT FROM AUTHOR]

It is challenging to use formic acid as a hydrogen donor for reduction reactions over heterogeneous non-noble metal catalysts. Herein, a nitrogen-doped carbon encapsulated cobalt nanoparticle catalyst was found to be effective for catalytic transfer hydrodeoxygenation reactions with formic acid under mild conditions. After protection with a carbon layer, the Co nanoparticles became resistant to formic acid. Furthermore, the nitrogen atoms in the catalyst served as base sites, assisting the cobalt nanoparticles in transfer hydrogenation reactions. [ABSTRACT FROM AUTHOR]

Evolutionary structure searches reveal that at 20 GPa, formic acid (FA) transforms to an orthorhombic ether-chain polymer phase, ruling out hydrogen bond symmetrization, followed by a novel crowned cyclic-ether tetragonal phase above 60 GPa. Emergence of characteristic polyether and new OH stretching modes in infrared experiments validate the findings. Resemblance of polymer chain with a cosmopolymer polyoxymethylene, shows an engrossing multifaceted evolution of FA. [ABSTRACT FROM AUTHOR]

In this study, we present a facile formic acid treatment to rejuvenate aged graphite anodes from spent lithium-ion batteries (LIBs) without damaging the electrode structure. This method effectively removes the interfacial blocking layer, improving capacity and rate performance. Our approach contributes to sustainable battery recycling strategies for spent graphite anodes in LIBs. [ABSTRACT FROM AUTHOR]

Direct conversion of CO2 into pure formic acid (FA) solution in the absence of base additives is of great significance, but is challenging due to thermodynamic limitations. Here, we have synthesized ultrafine Pd nano-catalysts modified with three kinds of amine groups, including a primary amine (PA), secondary amine (SA) and tertiary amine (TA), which realized the efficient hydrogenation of CO2 to pure FA in water at room temperature for the first time. Comprehensive characterizations reveal that all the amine groups are beneficial to the formation of ultrafine and uniform Pd nanoclusters (<2 nm), and that the electron-richness of Pd has a competitive effect with the steric hindrance of the amine groups on the CO2 hydrogenation activity. The SA-modified catalyst Pd/AC-SA, which has a lower binding energy of N and lower steric hindrance, thus shows the best turnover frequency (TOF) of 29.1 h−1 at 298 K and 4.0 MPa, which is even comparable to that of reported heterogeneous catalysts with base additives under harsh conditions. The DFT calculations further revealed the mechanism of CO2 hydrogenation; the first H-atom hydrogenation is the rate-determining step, which is in good agreement with the experiments. This work, as a successful example of the direct generation of pure FA solution at room temperature, exhibits great potential for future large-scale hydrogen storage. [ABSTRACT FROM AUTHOR]

We report an iridium system constructed around a long-tethered PGeP ligand that facilitates access to the less common germylene form, so far unreported for an 'NHC-type' Ge ligand. Its bonding is substantiated by computational studies and we have demonstrated its use for the catalytic dehydrogenation of formic acid, highlighting the potential of this underdeveloped type of ligand. [ABSTRACT FROM AUTHOR]

This work reports the interaction of γ-rays with MoO3 in several solvents to obtain non-stoichiometric (sub-oxide) MoO3−x through a one-pot synthesis. The effect of different doses of γ-radiation (30–90 kGy) with different protic solvents (water, N,N-dimethylformamide and formic acid) was investigated. Structural modifications were characterized by X-ray diffractometry and scanning electron microscopy while optical properties were investigated by UV-Vis spectroscopy. The analysis of the highly intense (020), (040) and (060) diffraction peaks suggests that there is a reduction in water and formic acid allowing the formation of MoO3−x nanosheets. Additionally, the photothermal response of MoO3−x obtained under different conditions was characterized, and a possible mechanism to explain the interaction of γ-rays with solvents and the oxide structure by oxidative/reductive processes in the solution was proposed. [ABSTRACT FROM AUTHOR]

Improper disposal of large quantities of crustacean shell waste from the food industry has caused serious environmental problems and waste of resources. Shell biorefinery is an emerging concept that upcycles the major components of crustacean shell waste, such as chitin, into value-added chemicals and materials. Producing biomass-derived 5-hydroxymethylfurfural (HMF) has been a hot topic over the past decades, while efficient conversion of shell-derived chitin into HMF is not available due to its water-insoluble and chemically-stable features. Herein, we develop a sustainable and efficient HMF production route from chitin. Chitin was treated with formic acid under mild conditions to synthesize formylated chitin (FC), which was subsequently converted to HMF in dimethyl sulfoxide (DMSO)–H2O media. Results showed that FC achieved a 53.2% HMF yield at 160 °C for 10 min catalyzed by AlCl3 in the co-solvent system (DMSO : H2O = 4 : 1, v/v), which is 11 times higher than the yield obtained from chitin under the same condition. The grafted formyl groups on FC significantly enhanced its noncovalent interactions with DMSO molecules, enhancing the accessibility and reactivity for HMF production. The reaction mechanisms were proposed and simulated with density functional theory calculations, and the intramolecular hydrogen migration is the rate-determining step in the reaction pathways. This study highlights a green and simple approach for chitin valorization. [ABSTRACT FROM AUTHOR]

The iridium(III) complexes [Ir(H)(Cl)(κ2-NSitBu2)(κ2-bipyMe2)] (2) and [Ir(H)(OTf)(κ2-NSitBu2)(κ2-bipyMe2)] (3) (NSitBu2 = {4-methylpyridine-2-yloxy}ditertbutylsilyl) have been synthesized and characterized including X-ray studies of 3. A comparative study of the catalytic activity of complexes 2, 3, [Ir(H)(OTf)(κ2-NSitBu2)(coe)] (4), and [Ir(H)(OTf)(κ2-NSitBu2)(PCy3)] (5) (0.1 mol%) as catalysts precursors for the solventless formic acid dehydrogenation (FADH) in the presence of Et3N (40 mol%) at 353 K has been performed. The highest activity (TOF5 min ≈ 3260 h−1) has been obtained with 3 at 373 K. However, at that temperature the FTIR spectra show traces of CO together with the desired products (H2 and CO2). Thus, the best performance was achieved at 353 K (TOF5 min ≈ 1210 h−1 and no observable CO). Kinetic studies at variable temperature show that the activation energy of the 3-catalyzed FADH process is 16.76 kcal mol−1. Kinetic isotopic effect (5 min) values of 1.6, 4.5, and 4.2 were obtained for the 3-catalyzed dehydrogenation of HCOOD, DCOOH, and DCOOD, respectively, at 353 K. The strong KIE found for DCOOH and DCOOD evidenced that the hydride transfer from the C–H bond of formic acid to the metal is the rate-determining step of the process. [ABSTRACT FROM AUTHOR]

Calcite is widely used in many fields. The synthesis of calcite is strongly influenced by solvents and additives. In this paper, the adsorption of water and formic acid molecules on the (104) surface of calcite was systematically studied on the atomic scale using the density functional theory (DFT) method. The results show that both molecules can be adsorbed on the calcite surface by occupying the top position of Ca. The results of differential charge density and the projected crystal orbital Hamiltonian population show that the adsorption is controlled by the charge transfer from the oxygen atom to the surface calcium. Formic acid has a carbonyl oxygen and it plays a greater role in stabilizing the surface than water. Moreover, the adsorption of two molecules can be further stabilized by hydrogen bonds formed between the hydrogen atom in the adsorbed molecules and the oxygen in calcite. This work provides a clear understanding of the stabilization of the calcite surface by adsorbing different molecules and also provides the possibility of tuning the synthesis of calcite by choosing a suitable solvent and additives. [ABSTRACT FROM AUTHOR]

A non-noble-metal modulation strategy has been developed to adjust the electronic structure of Pd, resulting in enhancement of the catalytic performances for the dehydrogenation of formic acid. Pd0.95Ni0.05/KBLA with a particle size of ∼1.25 nm exhibited the highest catalytic activity with a turnover frequency of 5432 h−1 at 50 °C. [ABSTRACT FROM AUTHOR]

New Ir complexes bearing N-(methylsulfonyl)-2-pyridinecarboxamide (C1) and N-(phenylsulfonyl)-2-pyridinecarboxamide (C2) were employed as catalysts for aqueous formic acid dehydrogenation (FADH). The ligands were designed to maintain the picolinamide skeleton and introduce strong sigma sulfonamide moieties. C1 and C2 exhibited good stability towards air and concentrated formic acid (FA). During 20 continuous cycles, C1 and C2 could achieve the complete conversion of FA with TONs of 172 916 and 172 187, respectively. C1 achieved a high TOF of 19 500 h−1 at 90 °C and an air-stable Ir–H species was observed by 1H NMR spectroscopy. [ABSTRACT FROM AUTHOR]

The transformation of lignin into value-added chemicals represents one of the relevant approaches for sustainable development. Herein, we prepared and characterized cobalt (Co–N–C) catalysts and evaluated their activity in transfer hydrogenolysis reactions using formic acid as the hydrogen donor with excellent activity and high selectivity for the C–O bond cleavage of lignin and lignin model compounds using water/ethanol or propylene carbonate as the solvents. Among them, the subnanometric Co-1 (CoIINx) catalyst was found to have a low content of cobalt of around 0.60 wt%, while demonstrating the highest activity in guaiacylglycerol-β-guaiacyl hydrogenolysis to selectively obtain guaiacol and isoeugenol. [ABSTRACT FROM AUTHOR]

The selective hydrogenation of nitrobenzene to aniline with formic acid over carbon-based metal-free catalysts was realized. Excellent catalytic performance was achieved over a catalyst prepared at 900 °C. The superior catalytic performance was attributed to the synergistic effect between graphitic nitrogen and pyridinic nitrogen. [ABSTRACT FROM AUTHOR]

This contribution deals with a new atom efficient two-stage production route for green methanol (MeOH) from biomass that includes biomass conversion to methyl formate (MF)/formic acid (FA) mixtures followed by hydrogenolysis to MeOH. Herein, we focus on the hydrogenolysis step and propose a materials solution to the problem of catalyst corrosion by the acidic MF/FA mixture formed in the previous biomass oxidation step. We show that Cu0.9Al2O4 spinel materials are very effective hydrogenolysis catalysts for the conversion of MA/FA mixtures to MeOH. Compared to commercial catalysts such as CuO/Cr2O3, the spinel material does not contain hazardous chromium compounds or require them during synthesis. Furthermore, this spinel catalyst shows much lower corrosion than known commercial hydrogenolysis catalysts. By using reactive frontal chromatography, nitrogen sorption, IR-ATR and XRD measurements, we show that CuO/MgO/ZnO/Al2O3 and CuO/Cr2O3 suffer from leaching of copper and chromium in the presence of FA due to the formation of mobile metal formate species. In contrast, the strongly fixed nature of copper in the highly ordered crystal structure of our Cu0.9Al2O4 spinel type catalyst leads to exceptional stability in the presence of FA and in continuous hydrogenolysis experiments for more than 110 h time-on-stream. [ABSTRACT FROM AUTHOR]