Bridge Bonds Research Articles

Atomic surface achieved through a novel cross-scale model from macroscale to nanoscale.

Chemical mechanical polishing (CMP) is widely used to achieve an atomic surface globally, yet its cross-scale polishing mechanisms are elusive. Moreover, traditional CMP normally employs toxic and corrosive slurries, resulting in potential pollution to the environment. To overcome these challenges, a novel cross-scale model from the millimeter to nanometer scale is proposed, which was confirmed by a newly developed green CMP process. The developed CMP slurry consisted of hydrogen peroxide, sodium carbonate, sodium hydroxycellulose, and silica. Prior to CMP, fused silica was polished by a ceria slurry. After CMP, the surface roughness (Sa) was 0.126 nm, the material-removal rate was 88.3 nm min-1, and the thickness of the damaged layer was 8.8 nm. The proposed model was built by fibers, through integrating Eulerian and Lagrangian models and reactive force field-molecular dynamics. The results predicted by the model were in good agreement with those of CMP experimentally. A model for large-sized fibers revealed that a direct contact area of 11.12% was obtained for a non-woven polishing pad during the CMP experiments. Another model constructed via combining Eulerian and Lagrangian functions showed that the stress at the intersections of the fibers varied mainly from 0.1 to 0.01 MPa and was higher than the stress at other parts. An increase in viscosity led to a decrease in the areas with low stress, demonstrating that viscosity enhanced the stress and facilitated the removal of material. At the microscale and nanoscale, the stress of the abrasive surface exposed to the workpiece changed from 2.21 to 6.43 GPa. Stress at the interface contributed to the formation of bridging bonds, further promoting the removal of material. With increasing the compressive stress, the material-removal form was transformed from a single atom to molecular chains. The proposed model and developed green CMP offer new insights to understand the cross-scale polishing mechanism, as well as for designing and manufacturing novel polishing slurries, pads, and setups.

Interfacial Co–O–Fe bonding in novel amorphous NiCo-ZIF@MIL-100 as efficient active sites enabling electrocatalytic water oxidation

The composite NiCo-ZIF@MIL with Co–O–Fe bridge bonds exhibits excellent catalytic activity (η ≈ 139 mV @ 10 mA cm−2).

Layered MOF supported on 2D delaminated MXene (Mo2Ti2C3) nanosheets boosted water splitting.

Metal organic frameworks (MOFs) have a porous structure, high surface area, and high charge transfer, and they have been regarded as model electrocatalysts. Optimization of the electrocatalytic activity of MOFs is challenging, and an effective strategy for this optimization is the construction of a well-defined interfacial bond bridge. In this work, an in situ approach of composite synthesis is reported for MOF (CoNiNH2BDC) with MXenes (Mo2Ti2C3), as the electrocatalytic properties of MOF can be greatly enhanced with the incorporation of the conductive material MXene. The prepared composite material was characterized thoroughly using XRD, XPS, FESEM, EDX, TEM, and BET. The synergistic effect of both components of this composite material resulted in enhanced conductivity and the number of active sites, which led to enhanced electrocatalytic performance. The CoNiNH2BDC MOF with different ratios of Mo2Ti2C3 MXene were synthesized, and the resulting materials were evaluated for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) activities. It was observed that the MOFMX3 attained a 10 mA cm-2 current density at 1.44 V for OER and -0.037 V for HER (vs. RHE), and lower values of Tafel slopes of 44.8 mV dec-1 for OER and 45 mV dec-1 for HER in 0.1 M KOH were achieved. The higher double layer capacitance (C dl) values lead to high electrochemical surface area (ECSA) values. Lower Tafel slope values for MOFMX3 show that the presence of MXene nanosheets in the hybrid provides support to the layered and porous configuration of MOF, and the chances of the interaction of electrolyte to the catalytically active sites are significantly enhanced. This work highlights the idea of growing bimetallic MOFs on Mo2Ti2C3 MXene using an interdiffusion reaction strategy and opens up an avenue for designing highly electrocatalytic systems.

Thiourea induced the N/S co-doped carbon skeleton suppressing the dissolution of V to boost superior cyclic stability of Na3V2(PO4)3

Currently, poor conductivity property and volume collapse have severly hindered development of Na3V2(PO4)3. Meanwhile, the dissolution of active V leads to the unstable cyclic performance. Traditional modified methods using carbon-based materials only elevate the electronic conductivity, without considering the interaction between carbon skeleton and Na3V2(PO4)3 grains. In this work, the in-situ modified carbon skeleton by N/S diatomic doped derived from thiourea is successfully synthesized through a facile sol-gel route. Significantly, the synergistic effects of N and S elements can provide more defects and active sites in carbon substrate, stimulating more Na+ to participate the electrochemical process. Moreover, the in-situ N/S co-doping strategy promotes amorphous carbon converting to graphitized carbon, effectively accelerating electronic conductivity. Especially, a coral morphology is formed during sintering process, coming from the pyrolysis effect of thiourea. The porous construction can promote the infiltration of electrolyte, enlarging the contact surface areas between particles and electrolyte. Meanwhile, the generated micropores can relieve the pressure from the shrinkage of crystal to enhance the structural stability. More importantly, due to the introduction of S in carbon substrate, stable C–S–C bonds can be formed between carbon molecular layers to increase the layer distance, benefiting for Na+ migration. Notably, a strong C–S–V bridge bond connection is generated that combines Na3V2(PO4)3 and carbon materials, inhibiting the dissolution of V in electrolyte, resulting in superior cyclic stability. NVP/C@N,S-10 % submits high capacities of 90.5 mAh g−1 and 75.9 mAh g−1 at 60 and 80C, remaining 59.2 mAh g−1 and 57.9 mAh g−1 after 20,000 cycles.

Ascorbic-acid-assisted in-situ construction of S-scheme CuO/Cu2O hetero-nanosheets with active Cu(II)-O-Cu(I) bridges for efficient CO2 photoreduction

Efficient charge transfer across interfaces is highly desirable, but remains challenging in engineering semiconductor heterojunctions for photocatalysis. In this work, hybrid hetero-nanosheets (HNSs) of CuO/Cu2O bridged with interfacial Cu(II)-O-Cu(I) have been constructed via an in-situ topotactic transformation strategy, in which CuO nanosheets are partially reduced by ascorbic acid and transformed into Cu2O. The interfacial Cu(II)-O-Cu(I) bridges are found to provide fast transfer channels for photogenerated carriers transporting from CuO to Cu2O in an S-scheme pathway, leading to enhanced separation of photogenerated carriers. Furthermore, the bond bridges can tune the kinetic and thermodynamic processes of the CO2-to-CO conversion at interfacial Cu(I) catalytic sites by altering the rate-determined step and shifting downwards d-band center of the Cu(I) sites. Owing to the interfacial Cu(II)-O-Cu(I) bridges, the optimized CuO/Cu2O HNSs significantly expedite the CO2 photoreduction to CO, delivering a CO2 conversion rate of 22.14 μmol g−1 h−1 with a CO selectivity of 94.4%, outperforming the state-of-the-art copper oxide-based photocatalysts. This work demonstrates an effective in-situ topotactic transformation strategy to create interfacial bond bridges at heterogeneous interfaces for boosted photocatalysis as well as the critical roles of interface catalytic sites for CO2 conversion.

Strategy for Remediation of Polychlorinated Biphenyls-Contaminated Soil Through Redox Management Based on Electronegativity of the Contaminants.

Literature review reveals that Persistent Organic Pollutants (POPs), such as polychlorinated biphenyls (PCBs), are electron deficient compounds due to the presence of highly electronegative groups. Hence, they are more amenable to anaerobic biodegradation rather than oxidative metabolism. However, the studies on PCBs bioremediation are more inclined towards aerobic treatment. Besides, the past studies are mainly centered on screening and application of PCB-degrading microorganisms. In our opinion the degradative capacity is already present in the native microflora, and choice of electron donor is of paramount importance for faster reductive metabolism of PCBs. In this study, the use of methanol as electron donor with cow dung as the general microbial inoculum resulted in high specific rate of degradation (0.0542-0.0637 /day) for high-chlorinated biphenyls. The % removal of PCBs ranged between 67.7 and 71.7%. It may be the first study on the application of methanol as a cheap electron donor for PCBs biodegradation without bioaugmentation with specifically selected microorganisms.

Comparison of aluminum formate and traditional aluminum coagulants in structure, hydrolysates, coagulation behavior, and its corrosion resistance advantage

Aluminum formate (AF) has been considered as a superior coagulant that can decompose under the UV light without causing equipment corrosion during water treatment. The main components of the aluminum formate coagulant are aluminum formate (C3H3AlO6), aluminum formate hydrate (C3H3AlO6·3H2O), and aluminum hydrogen formate (C3H3AlO6·2H2O2). Analysis of the hydrolyzed products revealed that the content of added formic acid during the synthesis of aluminum formate is a crucial factor influencing its coagulation effectiveness. Increasing the HCOOH/Al ratio from 1.5 to 4.0 resulted in smaller mass-to-charge ratio (m/z) and higher positive charge for AF hydrolysates, with fewer undetected aluminum species present. Hydrolysates of AF 1.5 exhibited similar characteristics to those of aluminum polychloride, while AF 3.0 demonstrated optimal glucan removal efficiency (>55 %) through physical absorption rather than chemical bond bridging as the primary coagulation mechanism. The jar test results for bovine serum albumin (BSA) coagulation removal indicated a decrease in removal efficiency as the HCOOH/Al molar ratio increased from 1.5 to 4.0, accompanied by a decrease in pH conditions from 6.35 to 7.27. The highest BSA removal efficiency (58 %) was achieved using AF 1.5 at pH 6.35, suggesting that BSA molecules were captured by aluminum formate through chemical bonds such as NO-Al-, Al2(SO4)3, unlike the physical absorption effect observed in glucan coagulation process. Furthermore, it should be noted that compared to traditional aluminum salt coagulants, aluminum formate exhibits excellent pipeline corrosion resistance properties.

In-depth understanding of the microscopic mechanism of biochar carbonaceous structures during thermochemical conversion: Pyrolysis, combustion and gasification

The thermochemical utilization of biomass char is vital for addressing environmental pollution and the energy crisis. The carbonaceous structure plays a crucial role in this process, and understanding the conversion mechanism aids in optimizing biomass reactors. This study performs a comprehensive analysis of high-temperature rice husk char using 13C NMR, XPS, and FTIR techniques. The carbonaceous structure is classified based on carbon bonding modes and the forms of O and N. The reaction mechanisms of thermochemical transformations under various atmospheres (N2, O2, CO2, H2O) are investigated using ReaxFF-MD. The reaction characteristics are determined, and the reaction activities are compared. The results indicate that the nitrogen-containing heterocycles remain in pyridine-type pyrolysis products under the N2 atmosphere (pyrolysis). Repolymerization occurs in the initial stages of pyrolysis, with the size of aromatic rings affecting the formation of heavy components. Under the O2 atmosphere (combustion), the degree of complete carbon oxidation is linked to the number of aromatic rings. The reactivity of aliphatic carbonaceous structures depends on the hydrogen content. Under the CO2 atmosphere (gasification), the pyrrole-type structure exhibits the highest gasification activity. Aromatic structures with oxygen functional groups are more susceptible to reacting with CO2, indicating higher sensitivity. Aliphatic H atoms tend to be oxidized into H2O. Under the H2O atmosphere (gasification), hydrogen in the gasification of aromatic carbon primarily originates from H at the aromatic boundary. In N2 and CO2 atmospheres, the CO bridge bond breaks first, followed by reactions. In H2O gasification, the breaking of bridge bonds connected to aliphatic carbon occurs simultaneously with gasification. Each reaction system's product distribution and elemental migration processes are also determined. The findings provide valuable theoretical insights into the application of biomass char.

Flexible Li-CO2 Batteries with Boosted Reaction Kinetics and Cyclelife Enabled by Heterostructured Mo3N2@TiN Cathode and Interface-protected Li Anode.

With theoretically endowing with high energy densities and environmentally friendly carbon neutralization ability, flexible fiber-shaped Li-CO2 battery emerges as a multipurpose platform for next-generation wearable electronics. Nevertheless, the ineluctable issues faced by cathode catalysts and Li anodes have brought enormous obstacles to the development of flexible fiber-shaped Li-CO2 batteries. Herein, a flexible fiber-shaped Li-CO2 battery based on Mo3N2 cathode coating with atomic layer deposited TiN and Li3N protected Li anode is constructed. Owing to the regulation surface electrons of Mo3N2 by TiN, heterostructured cathode has more delocalized electrons which enable cathodes to stabilize 2-electron intermediate products Li2C2O4 by electron bridge bonds and avoid disproportionation into Li2CO3. Li3N layers not only accelerate Li+ transportation but also avoid contact between Li and CO2 to form Li2CO3. Thus, the constructed Li-CO2 battery demonstrates a low charge potential of 3.22V, low overpotential of 0.56V, outstanding rate capabilities up to 1Ag-1, and excellent long-term cycling (≈2000h) with an energy efficiency of ≈80%. The fabricated flexible fiber-shaped Li-CO2 battery shows an ultrahigh energy density of 14772.5Whkg-1 based on cathodes (340.8Whkg-1 based on device mass), and outstanding deformations adaptability, giving it great potential for wearable electronics.

Pretreatment of pine needles via torrefaction, oxidation and hydrothermal carbonization at 250 °C impacts subsequent pyrolysis and activation in distinct ways

Thermal pretreatment of biomass in varied medium (i.e. nitrogen, air or water) might further impact pyrolysis and activation in distinct ways. Herein, hydrothermal carbonization (HTC) or torrefaction of pine needles in nitrogen or air at 250 °C and further pyrolysis/activation of pretreated samples was conducted. The results indicated yield of solid followed the method of pretreatment: torrefaction > oxidation > HTC, due to significant oxidation of aliphatics in the pretreatment in air and structural reconstruction in HTC. Additionally, pretreatment in air remarkably increased overall production of biochar (35.1 %), owing to enhanced resistivity to cracking. HTC released nearly half of organics, leading to remarkably lower overall yields of biochar than that in blank experiment (24.7 % versus 30.6 %), but increased thermal stability of biochar through enhancing aromatic degree. Additionally, pretreatment in air removed some H species via oxidation but not nitrogen species while the HTC was the opposite while induced leaching of inorganics. In-situ IR characterization indicated conversion of aliphatic -OH to phenolic -OH in nitrogen-pretreatment, oxidation of ether bridging bond between benzene rings in air-pretreatment and formation of thermally carbonyls via HTC. During activation, all the pretreatments reduced specific surface area of activated carbon, following the order: blank (1351.1 m2 g−1) > torrefaction in N2 (1314.7 m2 g−1) > oxidation in air (1293.8 m2 g−1) > HTC (1218.2 m2 g−1). Oxidation or aromatization reactions in the pretreatment increased aromatic degree of the feedstock, making pore generation via cracking more difficult. Besides, pretreatments also changed morphologies of resulting biochar or activated carbon in distinct ways.

Self-Constructing 100% Water-Resistant Metal Sulfides through In Situ Acid Etching for Effective Elemental Mercury (Hg0) Capture.

Metal sulfides (MSs) can efficiently entrap thiophilic components, such as elemental mercury (Hg0), and realize environmental remediation. However, there is still a critical problem challenging the extensive application of MSs in related areas, i.e., how to self-regulate their water (H2O) resistance without complexing the sorbent preparation procedure. This work for the first time developed an in situ acid-etching method that self-engineered the water affinity of MSs through changing the interfacial interaction between MSs and Hg0/H2O. The introduction of abundant, undercoordinated sulfur onto the sorbent surface was the primary reason accounting for the significantly improved H2O resistance. The high surface coverage of undercoordinated sulfur induced the formation of polysulfur chains (Sx2-) that stabilized Hg0 via a bridging bond and repelled H2O, attributed to the favorable electron configurations. These properties made the surface of MSs highly hydrophobic and increased the adsorption selectivity toward Hg0 over H2O. The MSs exhibited 100% H2O resistance even in the presence of 20% H2O, which is much higher than the H2O concentration under most practical scenarios. From these perspectives, this work for the first time overcame the detrimental effects of H2O on MSs through a self-regulating way that is scalable and negligibly complexes the sorbent preparation pathway. The highly water-resistant and cost-effective MSs as prepared can serve as efficient Hg0 removal from industrial flue gas in the future.

Revealing the conformational dynamics of UDP-GlcNAc recognition by O-GlcNAc transferase via Markov state model

The O-linked N-acetylglucosamine (O-GlcNAc) glycosylation is a critical post-translational modification and closely linked to various physiological and pathological conditions. The O-GlcNAc transferase (OGT) functions as the only glycosyltransferase of O-GlcNAc glycosylation by transferring GlcNAc from UDP-GlcNAc to serine or threonine residues on protein substrates. The interaction mode of UDP-GlcNAc against OGT has been preliminarily revealed by the crystal structures, yet an atomic-level comprehension for the conformational dynamics of the recognition process remains elusive. Here, we construct the Markov state model based on extensive all-atom molecular dynamics (MD) simulations with an aggregated simulation time of ∼9 μs, and reveal that the UDP-GlcNAc recognition process by OGT encompasses four key metastable states, occurring within an estimated timescale of ∼10 μs. During UDP-GlcNAc recognition process, we find the pyrophosphate moiety (P2O52−) initially anchors to the active pocket via salt bridge and hydrogen bonds, facilitating subsequent binding of the uridine and GlcNAc moieties. Furthermore, the functional roles of K842 involved in the salt bridge with P2O52− were evaluated through extra mutant MD simulations. Overall, our study provides valuable insights into the UDP-GlcNAc recognition mechanism by OGT, which could further aid in mechanistic studies of O-GlcNAc glycosylation and drug development targeting on OGT.

Oblique impact breakage unification of nonspherical particles using discrete element method

Particle breakage commonly occurs during processing of particulate materials, but a mechanistic model of particle impact breakage is not fully established. This article presents oblique impact breakage characteristics of nonspherical particles using discrete element method (DEM) simulations. Three different particle shapes, i.e. spherical, cuboidal and cylindrical, are investigated. Constituent spheres are agglomerated with bridging bonds to model the breakage characteristics under impact conditions. The effect of agglomerate shapes on the breakage pattern, damage ratio, and fragment size distribution is fully investigated. By using a newly proposed oblique impact model, unified breakage master surfaces are theoretically constructed for all the particle shapes under oblique impact conditions. The developed approach can be applied to modelling particulate processes where nonspherical particles and oblique impact breakage are prevailing.

Sweeny dynamics for the random-cluster model with small Q.

The Sweeny algorithm for the Q-state random-cluster model in two dimensions is shown to exhibit a rich mixture of critical dynamical scaling behaviors. As Q decreases, the so-called critical speeding-up for nonlocal quantities becomes more and more pronounced. However, for some quantity of a specific local pattern, e.g., the number of half faces on the square lattice, we observe that, as Q→0, the integrated autocorrelation time τ diverges as Q^{-ζ}, with ζ≃1/2, leading to the nonergodicity of the Sweeny method for Q→0. Such Q-dependent critical slowing-down, attributed to the peculiar form of the critical bond weight v=sqrt[Q], can be eliminated by a combination of the Sweeny and the Kawasaki algorithm. Moreover, by classifying the occupied bonds into bridge bonds and backbone bonds, and the empty bonds into internal-perimeter bonds and external-perimeter bonds, one can formulate an improved version of the Sweeny-Kawasaki method such that the autocorrelation time for any quantity is of order O(1).

A Multifunctional Hydrogen Bond Bridge Interface to Achieving Efficient and Stable Perovskite Solar Cells

AbstractIn perovskite solar cells (PSCs), the buried interface between the electron transfer layer (ETL) and perovskite (PVK) layer profoundly affects the charge carrier transfer efficiency, which has significant implications for the efficiency and long‐term stability of the device. Herein, an organic chemical compound 4,6‐diamino‐2‐mercaptosine (DMP) is incorporated into the ETL/PVK interface in order to optimize the interfacial performance through a hydrogen bond bridging junction. DMP is tightly anchored to the ETL surface by forming the intermolecular hydrogen bonding with the structure as N─H∙∙∙N. This bridge connection is beneficial for enhancing the interface contact, further restraining severe nonradiative charge recombination. Synchronously, the interaction of ─SH with uncoordinated Pb2+ passivates the defects on the bottom layer of perovskite, further regulating the perovskite crystal growth. Overall, the results express that the power conversion efficiency (PCE) of PSCs based on the DMP interface has significantly increased to 21.65% without obvious hysteresis. Meanwhile, the unencapsulated modified devices show superior environmental stability, maintaining over 85% of their initial PCE even after 500 h in an atmospheric environment.

Green preparation of new pyrimidine triazole derivatives via one-pot multicomponent reactions of guanidine.

In this research the goal was to produce novel pyrimidine triazole compounds in high yields using triethylamin as an efficient catalyst. These new compounds were synthesized by using multicomponent reaction of aldehydes, guanidine, electron deficient acetylenic compounds, tert-butyl isocyanide and hydrazonoyle chloride in aqueous media. Due to the presence of an NH group, which was assessed using two different methodologies, newly synthesized pyrimidine triazoles have antioxidant properties. Additionally, the antibacterial activity of newly created pyrimidine triazoles was assessed using the disk distribution method with two different types of Gram-positive bacteria and Gram-negative bacteria, demonstrating that the use of these compounds prevented the growth of bacteria. Applied to the preparation of pyrimidine triazole derivatives, this method has short reaction times, high product yields, and the ability to separate catalyst and product using simple procedures.

Effects of temperature and strain rate on dynamic crack propagation in brittle silicon

Based on molecular dynamics, this study investigates the brittle fracture of silicon as a function of temperature and strain rate from an atomic perspective. The fracture toughness increases with increasing temperature, whereas the opposite trend is observed at a higher strain rate. When the critical state is reached, the atomic structures and stress concentration at the sharp crack tip determine crack path selection. The (111)[11̅0] crack system propagates in a straight line owing to the sequential breaking of only the maximum stressed bond directly in front of the crack. By contrast, the (110)[1̅10] crack system propagates in a straight line or is deflected among different cleavage planes owing to the breaking of two highly stressed bridging bonds. In addition, the corresponding velocity of the crack tip may be affected by these two factors; essentially, it increases at higher temperatures and strain rates.

Oxygen-driven bulk defect engineering in carbon to reduce voltage hysteresis for fast potassium storage at low voltage

Reducing the voltage hysteresis and enhancing the rate performance of carbon anode materials are critical for boosting the energy and power density of potassium-ion full-cell devices. In this study, we report an oxygen-driven bulk defect engineering in carbon to reduce the voltage hysteresis, enabling reversible and fast potassium storage at low voltage. Through high-concentration hydrothermal treatment, the oxidized pitch structure units undergo a process where oxygen bridge bonds are formed, resulting in the creation of interconnected bulk structures. The oxygen-containing functional groups are removed during carbonization, thereby introducing bulk defects into the carbon materials to enhance the kinetics of K+ insertion in the nanographite domains. The bulk carbon anode achieves low voltage hysteresis, high reversible capacity below 1 V (248 mAh g−1 at 0.05 A g−1) and high-rate (192 mAh g−1 at 1 A g−1). Additionally, the full cell exhibits a discharge plateau at approximately 3.1 V and high cyclic stability (95 % capacity retention from the 10th to the 120th cycle). This study presents a novel approach for constructing bulk defects in carbon materials to achieve efficient potassium storage at low potential, thus advancing the application of advanced carbon anodes in potassium-ion batteries.

Understanding Bridging Sites and Accelerating Quantum Efficiency for Photocatalytic CO2 Reduction

HighlightsThe S-vacancies result in the change of d-band electronic state of Mo.An internal quantum efficiency of 94.01% at 380 nm for photocatalytic CO2 reduction reaction (CO2RR).The Mo–S bridging bonds optimize adsorption energies and accelerate CO2RR kinetics.

Structural conservation in the glutathione binding in Sphingomonas sp. glutaredoxin Grx3 and variations for cold adaptation

Glutaredoxin 3 (Grx3), a redox protein with a thioredoxin-fold structure, maintains structural integrity and glutathione (GSH) binding capabilities across varying habitat temperatures. The cis-Pro loop, essential for GSH binding, relies on the Arg-Asp salt bridge (α2-α3) and Gln-His hydrogen bond (β3-β4) for its conformation. In some psychrophilic Grx3 variants, Arg in α2 is replaced with Tyr, and His in β4 is replaced with Phe. This study examines the roles of these bonds in Grx3's structure, function, and cold adaptation, using SpGrx3 from the Arctic bacterium Sphingomonas sp. Despite its cold habitat, SpGrx3 maintains the Arg51-Asp69 salt bridge and Gln56-His63 hydrogen bond. The R51Y substitution disrupts the α2-α3 salt bridge, while the H63F and H63Y substitutions hinder the salt bridge through cation-π interactions with Arg51, involving Phe63/Tyr63, thereby enhancing flexibility. Conversely, mutations that disrupt the hydrogen bond (Q56A, H63A, and H63F) reduce thermal stability. In the psychrophilic Grx3 configuration A48T/R51Y/H63F, a Thr48-Gln56 hydrogen bond stabilizes the cis-Pro loop, enhancing flexibility by disrupting both bonds. Furthermore, all mutants exhibit reduced α-helical content and catalytic efficiency. In summary, the highly conserved Arg51-Asp69 salt bridge and Gln56-His63 hydrogen bond are crucial for stabilizing the cis-Pro loop and catalytic activity in SpGrx3. His63 is favored as it avoids cation-π interactions with Arg51, unlike Phe63/Tyr63. Psychrophilic Grx3 variants have adapted to cold environments by reducing GSH binding and increasing structural flexibility. These findings deepen our understanding of the structural conservation in Grx3 for GSH binding and the critical alterations required for cold adaptation.