MPa N2 Research Articles

Efficient hydrodeoxygenation of lignin-derived phenolics to cyclohexanol with N-doped alumina- carbide‐based RuCo catalysts derived from MOF under mild conditions

In this work, a novel RuCo bimetallic supported on N-doped carbon support containing alumina was prepared by in-situ pyrolysis using MOF-303 as the support precursor (Ru3Co1@CN-Al2O3), and it was applied to the efficient hydrodeoxygenation (HDO) of guaiacol under mild conditions (0.01 MPa H2, 200 °C, 3h), the yield of cyclohexanol reaches an impressive 83.12 %. In the absence of external hydrogen (2 MPa N2, 220 °C, 2 h), complete conversion of guaiacol was achieved, along with a remarkable 97.81 % selectivity towards cyclohexanol. The HDO of guaiacol under different atmospheres was further studied, and the possible mechanism was proposed. Characterization results indicated that the supported metals (Ru and Co) not only interacted with the N in the MOF-303 to enhance catalyst stability but also that the synergistic effect between Ru and Co was key to promoting the high yield of cyclohexanol through catalytic transfer hydrodeoxygenation (CTHDO) in isopropanol. Additionally, Ru3Co1@CN-Al2O3 was also effective in achieving the HDO of macromolecular lignin. This study provides a feasible approach for the high value-added green transformation of lignin and its derivatives under mild conditions, highlighting the significant potential of MOFs for lignin valorization.

Heteropoly Acid‐Based Ionic Liquid Catalyzes Cellulose into Levulinic Acid in a Bi‐Phase Solvent System

AbstractLevulinic acid is an important chemical intermediate, which has many applications in organic synthesis, industry, agriculture, and medicine. In this word, three kinds of heteropoly acid based ionic liquids ([IMPS]H2PW12O40、[PyPS] H2PW12O40 [TEAPS] H2PW12O40) were used to catalyze the one‐pot conversion of cellulose to levulinic acid. [IMPS]H2PW12O40 has the highest catalytic activity due to its strong Hammett acidity (H0). In addition, the effect of biphasic solvent systems on the conversion of cellulose to levulinic acid was also studied. The results showed that the GVL/H2O system could effectively promote the conversion of cellulose and increase the yield of levulinic acid. The yield of levulinic acid could reach 52.6% and the conversion rate of cellulose was 91.2% at 180 °C for 180 min under the GVL/H2O volume ratio of 1:1 with [IMPS]H2PW12O40 as a catalyst at 1 Mpa N2 and cellulose as raw material. And [IMPS]H2PW12O40 can be recycled up to five times without significant performance loss. This study provides a promising method for efficiently converting cellulose and other biomass resources to levulinic acid extraction.

Robust and orange-yellow-emitting Sr-rich polytypoid α-SiAlON (Sr3Si24Al6N40:Eu2+) phosphor for white LEDs

ABSTRACT Nitrides and oxynitrides isostructural to α-Si3N4 (M-α-SiAlON, M = Sr, Ca, Li) possess superb thermally stable photoluminescence (PL) properties, making them reliable phosphors for high-power solid-state lighting. However, the synthesis of phase-pure Sr-α-SiAlON still remains a great challenge and has only been reported for Sr below 1.35 at.% as the large size of Sr2+ ions tends to destabilize the α-SiAlON structure. Here, we succeeded to synthesize the single-phase powders of a unique ‘Sr-rich’ polytypoid α-SiAlON (Sr3Si24Al6N40:Eu2+) phosphor with three distinctive Sr/Eu luminescence sites using a solid-state remixing-reannealing process. The Sr content of this polytypoid structure exceeds those of a few previously reported structures by over 200%. The phase purity, composition, structure, and PL properties of this phosphor were investigated. A single phase can be obtained by firing the stoichiometric mixtures of all-nitride precursors at 2050°C under a 0.92 MPa N2 atmosphere. The Sr3Si24Al6N40:Eu2+ shows an intense orange-yellow emission, with the emission maximum of 590 nm and internal/external quantum efficiency of 66%/52% under 400 nm excitation. It also has a quite small thermal quenching, maintaining 93% emission intensity at 150°C. In comparison to Ca-α-SiAlON:Eu2+, this Sr counterpart shows superior quantum efficiency and thermal stability, enabling it to be an interesting orange-yellow down-conversion luminescent material for white LEDs. The experimental confirmation of the existence of such ‘Sr-rich’ SiAlON systems, in a single-phase powder form, paves the way for the design and synthesis of novel ‘Sr-rich’ SiAlON-based phosphor powders with unparalleled properties.

Lignin-MOF hybrid polymetallic composites for selective hydrogenolysis of cellulose derived 5-hydroxymethylfurfural

The development of green, effective and inexpensive catalysts was important for the catalytic transfer hydrogenation of 5-hydroxymethylfurfural (HMF) to prepare 5-methylfurfuryl alcohol (MFA). The assembly of sodium lignosulfonate (LS) with NiCo-MOFs through a simple hydrothermal method was reported, and a series of iron-containing polymetallic hybrid catalysts were investigated. The introduction of iron led to the increase of medium strong acid sites and Lewis acid sites in the catalyst and enhanced the adsorption of furan rings, thus improved the catalytic activity. The effects of calcination temperature, iron content, and reaction parameters (including reaction temperature, pressure, hydrogen donor solvent) were all studied in detail. It was found that HMF could be completely converted over Fe@Ni3Co-MOF-LS, with a MFA yield of 88.75 % under the optimal condition (240 ℃, 2 MPa N2 in 4 h) without the presence of hydrogen. This study provided a new perspective for the utilization of lignin resource as carbon-based catalysts for the production of biomass-derived platform chemicals.

Encapsulated metal-based MOF nanoparticles as efficient catalysts for catalytic transfer hydrodeoxygenation of lignin-derived vanillin to 2-methoxy-4-methylphenol

A range of carbon-encapsulated non-precious metal catalysts (Ni@C, Ce@C, Mo@C, and Zn@C) were prepared using the hydrothermal approach for the catalytic transfer hydrodeoxygenation of vanillin compound derived from lignin. The catalytic efficacy was affected by the level of acid sites, catalyst durability, and the cooperation with H-donor solvents. Analysis indicated that the thin carbon layer enclosing the active sites notably improved catalytic effectiveness and thermodynamic stability compared to alternative catalysts. Notably, Ni@C demonstrated superior catalytic performance, achieving a vanillin conversion rate of 98.72 % and an 87.12 % yield of the major product 2-methoxy-4-methylphenol under specific conditions (240 ℃, 2.0 MPa N2, ethanol as a solvent, 4-hour reaction time). These findings underscore the significant potential of carbon-wrapped MOF catalysts in advancing the sustainable utilization of lignin and fostering the growth of a more eco-friendly bioeconomy.

Palladium-modified zirconium dioxide as a selective catalyst for hydrogenation of furfural to furfuryl alcohol

The hydrogenation reaction can effectively promote the upgrading of biomass-derived resources into high value-added products. Currently, constructing metal Pd-based catalysts is one of the effective strategies to promote hydrogenation reactions. In this paper, Pd-ZrO2 catalyst was prepared through electrospinning technology using PdCl2-Zr(acac)4/PVP as a precursor for furfural hydrogenation reaction. The results revealed that the obtained Pd-ZrO2 catalyst could provide 70 % furfural conversion and 76.2 % furfuryl alcohol selectivity at 170 ℃ and 2 MPa 5 % H2/Ar for 12 h. At the same time, nearly complete FAL conversion with 92.9 % FOL selectivity could be achieved under 2 MPa N2 for 12 h in the process of catalytic transfer hydrogenation. In addition, the effects of conditions such as reaction temperature, reaction time, and solvent on the two hydrogenation paths were further evaluated. The cycle test proved that the catalyst can be recycled multiple times without significant decrease in catalytic activity.

Self-hydrogen transfer hydrogenolysis of β-O-4 bonds in lignin model compounds over NiCu/Al2O3 catalyst

Hydrogenolysis of β-O-4 linkages in lignin to produce aromatic compounds is attractive but challenging. Currently, external hydrogen source like hydrogen gas or hydrogen-donor solvent is necessary during hydrogenolysis, leading to high cost and low selectivity of products. Herein, a NiCu/Al2O3 catalyst was prepared for self-hydrogen transfer hydrogenolysis (SHTH) of Cβ-O bond using inherent CαH-OH structure as H-source. A β-O-4 model compound, 2-phenoxy-1-phenethanol, was completely transformed into acetophenone and phenol at 220 ℃ under 1 MPa N2 for 2h. The SHTH reaction proceeded through a dehydrogenation reaction followed by a hydrogenolysis reaction. Hydrogen radicals released from CαH-OH group generated a “hydrogen pool” on the catalyst surface, which inserted into the formed β-O-4 ketone intermediate to cleave the Cβ-O bond. The catalyst presented outstanding reusability and universality during the SHTH reaction. Moreover, the methoxy groups at aryl positions impeded the SHTH process, and the steric effect was related to the amount and position of methoxy groups. This study realizes the utilization of structural hydrogen from lignin model compounds for its Cβ-O bond cleavage, providing an economical and sustainable method toward lignin valorization.

Synergy of metallic Co and oxygen vacancy sites in Co/Ce-MOF catalysts for efficiently promoting lignin derived phenols and macromolecular lignin hydrodeoxygenation

The enhanced utilization of biomass-derived chemicals for the generation of high value aromatics through an advanced catalytic strategy has captured considerable attention within the realm of eco-friendly manufacturing. This work presented four innovative three-dimensional rod-shaped mesoporous Ce-based MOF materials, which were coupled with a H-donor solvent to facilitate vanillin hydrodeoxygenation and macromolecular lignin. Under the optimized conditions (30 mg CoCe@C catalyst, 2 MPa N2 pressure, 15 mL isopropanol, 190 °C, and 5 h), the CoCe@C catalyst achieved nearly complete conversion of vanillin and demonstrated 87.8 % selectivity in the hydrogen-donor solvent. The characterization findings suggested that the synergy between metallic Co and oxygen vacancy sites enabled the effective activation of CHO group in vanillin, leading to formation of reactive product MMP. In addition, the optimal CoCe@C catalyst could also achieve macromolecular lignin hydrodeoxygenation to obtain high yield of lignin oil products with narrower molecular weight distribution. This study presented a viable approach for the concurrent utilization of lignin derivatives in the generation of high value fuels and chemicals.

Ce-Doped Co-ZIF as an efficient catalyst for hydrodeoxygenation of lignin-derived phenols: From guaiacol to cyclohexanol

Through the utilization of diverse technological processes, lignin could be transformed into a multitude of valuable chemicals and fuels. This transformation not only reduces our dependence on fossil energy but also fosters the promotion of environmental sustainability. In this study, Ce metal was incorporated into the zeolite imidazolium framework-67 (ZIF-67) using the impregnation method to prepare a series of bimetallic catalysts. Using isopropanol solvent as the hydrogen source, guaiacol was effectively converted to cyclohexanol with over 80.0% selectivity over the optimum catalyst at 240 °C, 1.5 MPa N2, for 4 hours. The prepared catalysts were subjected to characterization methods such as BET, SEM, XPS, TEM, XRD, H2-TPR and NH3-TPD. The results of the characterization show that the addition of Ce changed the zeolitic imidazolium ester backbone structure of ZIF-67 and encouraged the emergence of more oxygen vacancies, which strengthened the catalyst hydrodeoxygenation activity and reducibility. Based on the findings of the catalytic performance tests and a retesting, the reaction pathway of the guaiacol hydrodeoxygenation process was suggested.

Double core–shell hollow nanocage CuO@Co3O4 for the selective hydrogenolysis of C–O bonds of lignin without external hydrogen

The design of a highly active Cu-Co catalyst for catalytic transfer hydrogenolysis of lignin without the use of external hydrogen remains highly challenging. In this work, Cu2O was initially encapsulated in ZIF-67, and subsequently Cu2O@ZIF-67 was utilized as a precursor and sacrificial template to prepare the unique double core–shell hollow nanocage CuO@Co3O4. Co and Cu, serving as Lewis acid sites and dehydrogenation sites for the hydrogen-donor solvent isopropanol, respectively, exhibited synergistic enhancement, further increasing the catalytic activity. Under the optimal conditions of 220 °C, 1 MPa N2, and 4 h, the catalyst achieved 100 % conversion of 2-phenoxy-1-phenylethanol and 100 % yield towards cyclohexanol and ethylbenzene. Furthermore, the catalyst remained stable and reusable after 5 cycles, providing a practicable guidance for the value-added conversion of lignin.

MOFs-derived carbon-covered nickel phosphide for catalytic transfer hydrodeoxygenation of lignin-derived vanillin

The catalytic transfer hydrodeoxygenation (CTH) of lignin and its derivates to biofuels and fine chemicals was a promising technology for efficient utilization of biomass. Herein, a series of MOFs derived carbon-covered Ni2P@C-x catalysts were successfully fabricated via chemical vapor deposition for the CTH of lignin-derived vanillin to produce 2-methoxy-4-methylphenol (MMP). Ni2P@C-3 catalyst exhibited an excellent CTH performance, obtaining nearly 100 % conversion of vanillin and 95 % yield of MMP under the conditions of 180 °C, 3 h, and 0 MPa N2 in an isopropanol environment. Based on characterization results, the high catalytic activity of Ni2P@C-3 catalyst was attributed to Niδ+ species owing to the electron transfer from Ni to P and the P-OH groups in Ni2P phase, which provided more Lewis acid sites and Brønsted acid sites. Moreover, the small particle size with high dispersion and surface carbon defects also promoted the CTH performance. This work could provide some useful insights for the hydrodeoxygenation of lignin and its derivatives in the future.

Heteropolyacids promoted MOF-derived high-performance Co(H4)@C-HPW0.25 catalysts for catalytic transfer hydrogenation of vanillin in mild condition

Catalytic transfer hydrogenation (CTH) was recognized as a promising technique for converting various lignin derivatives to fuels and high-value compounds in heterogeneous systems. Herein, Co@C catalysts with diverse organic ligands, Keggin-type heteropolyacids, acid addition quantities, and metal/organic ligand molar ratios were synthesized via one-pot hydrothermal processes and carbonization methods. The optimized catalyst demonstrated highly efficient active hydrogen generation from isopropanol and the best conversion (100 %) for vanillin (VAN) hydrodeoxygenation (HDO) with 90 % 2-methoxy-4-methylphenol (MMP) yield at 180 °C for one hour under mild conditions of 0 MPa N2 (hydrogen-free circumstance), which were strongly connected to the higher specific surface area (154.45 m2/g), acidic site density (4.67 mmol/g), and stronger metal-P interactions of the Co(H4)@C-HPW0.25 catalyst. The findings in this work provided an advanced thinking for designing high-performance non-noble-metal catalysts that could be applied in the catalytic HDO transformation of various biomass derivatives into green fuel and chemicals under mild circumstances.

Investigations on the oxidation behavior and removal mechanism of SiC/SiC composites by multi-pulse femtosecond laser ablation

SiC/SiC (SiC fiber-reinforced SiC matrix) composites have superior performance, making them promising candidates as one of the best materials for high-temperature components in aerospace applications. This investigation analyzed the morphology, structure, composition, and plasma state of multi-pulse femtosecond laser ablated SiC/SiC composites from multiple perspectives using various static and in situ characterization methods. Further, the oxidation behavior and removal mechanism of SiC/SiC composites were studied qualitatively and quantitatively. The results indicated that the ablation products of multi-pulse femtosecond laser ablation of SiC/SiC composites were mainly SiO2 and plasma deposits. The heat accumulation effect and oxidation degree at the ablation locations were enhanced accordingly as the effective ablation number or energy density increased, and the main shape of the products also changed regularly. At the same time, the material removal mechanism changed from non-thermal removal dominated to the equilibrium stage and then to thermal removal dominated. The detailed analysis of the oxidation behavior of each component in SiC/SiC composites enabled the controlled ablation of femtosecond lasers targeting the oxidation process of SiC/SiC composites. Besides, 1 MPa N2 could improve the processing efficiency of femtosecond laser for the depth and width of the groove by a maximum of about 90.40% and 104.02% in this study, respectively. Ultimately, the range of laser process parameters corresponding to multi-pulse femtosecond laser ablation of SiC/SiC composites without thermal removal as dominant was determined.

Lignin meets MOFs: Lignin derived metal carbon material for the catalytic hydrotreatment of guaiacol to cyclohexanol

Catalytic upgrading lignin-derived bio-oil with high oxygen content to directly usable transport fuel through hydrotreatment is highly desirable, but still remains a challenge. In this work, a series of Co-based catalysts were synthetized using metal–organic frameworks (MOFs) as a structure-directing agent and lignin as a renewable carbon precursor via a simple hydrothermal method. Among these catalysts, Co/C-EL-0.5–500 showed the best catalytic hydrotreatment activity, affording 100% guaiacol conversion with 90% cyclohexanol yield under the conditions of 240 °C, 0 MPa N2 and 4 h. According to the characterization results of XRD, SEM, TEM, BET, ICP, NH3-TPD and XPS, the excellent performance of Co/C-EL-0.5–500 was attributed to large specific surface area, small Co particle size, and optimal acidity. The possible reaction pathway was proposed based on the product distribution. In addition, isopropanol was used as H-donor instead of extra hydrogen, and we hope that it could provide a novel strategy for bio-oil upgrading.

Feasibility study on substitution of SF6 insulated current transformer with environment-friendly natural gas

Many SF6 gas-insulated current transformers (CT) are used in the power grid. The global warming potential (GWP) of SF6 is 23,900 times that of CO2, and the leakage of SF6 will aggravate the global warming trend. It is a hot issue to carry out the study of environment-friendly gas substitution in the power grid. This paper systematically studied the voltage withstand, partial discharge, and temperature rise characteristics of dry air, N2, and CO2 gas-insulated CTs. Through the study, the permissible critical pressures in environment-friendly gas-insulated CTs were determined to be 0.9 MPa for dry air, 0.7 MPa for N2, and 0.8 MPa for CO2, respectively. The partial discharge intensity was less than 5 pC for environment-friendly gas-insulated CTs at 0.3 MPa∼0.8 MPa pressure. The experimental results of temperature rise characteristics showed that under the condition of a 600A rated operating current, the maximum temperature rise of the CTs was about 80 °C, and the maximum temperature rise happened at the conductive rod. The experimental results verified that environment-friendly gases could meet the requirements of insulation and temperature rise. Due to the increase of pressure in CTs, the action pressure of the explosion-proof membrane should be changed to meet the mechanical strength requirements. It is recommended that when using 0.9 MPa dry air, the action pressure should be designed as 1.8 MPa; when using 0.7 MPa N2, the pressure should be designed as 1.4 MPa; when using 0.8 MPa CO2, the pressure should be designed as 1.6 MPa. The results of this paper can provide a reference for development of environment-friendly gas-insulated CTs.

Photoelectrochemical N2 -to-NH3 Fixation with High Efficiency and Rates via Optimized Si-Based System at Positive Potential versus Li0/.

As a widely used commodity chemical, ammonia is critical for producing nitrogen-containing fertilizers and serving as the promising zero-carbon energy carrier. Photoelectrochemical nitrogen reduction reaction (PEC NRR) can provide a solar-powered green and sustainable route for synthesis of ammonia (NH3 ). Herein, we report an optimum PEC system with a Si-based hierarchically-structured PdCu/TiO2 /Si photocathode and well-thought-out trifluoroethanol as the proton source for lithium-mediated PEC NRR, achieving a record high NH3 yield of 43.09μg cm-2 h-1 and an excellent faradaic efficiency of 46.15% under 0.12-MPa O2 and 3.88-MPa N2 at 0.07V versus lithium(0/+) redox couple (versus Li0/+ ). PEC measurements coupled with operando characterization revealed that the PdCu/TiO2 /Si photocathode under N2 pressures facilitate the reduction of N2 to form lithium nitride (Li3 N), which reacts with active protons to produce NH3 while releasing the Li+ to reinitiate the cycle of the PEC NRR. The Li-mediated PEC NRR process is further enhanced by introducing small amount of O2 or CO2 under pressure by accelerating the decomposition of Li3 N. For the first time, this work provides mechanistic understanding of the lithium-mediated PEC NRR process and opens new avenues for efficient solar-powered green conversion of N2 -to-NH3 . This article is protected by copyright. All rights reserved.

Efficient Lignin Depolymerization Process for Phenolic Products with Lignin-Based Catalysts and Mixed Solvents

Due to their diverse functional groups and structural composition, carbon-based catalysts exhibit superior performance in various catalytic reaction systems, such as hydrogenolysis, hydrogenation, and oxidation. Herein, we propose an effective strategy of lignin liquid-phase depolymerization by applying the designed lignin-based carbon catalysts to produce aromatic chemicals. A series of Ni–Mo bimetallic carbon-based catalysts were synthesized to explore the effect of different preparation methods on the catalytic activity. The results demonstrate that the embedded Ni–Mo/C-WMO catalyst with multi-active sites of Ni, MoO3, and Mo2C results in a prominent catalytic effect on lignin depolymerization. The Ni–Mo/C-WMO catalyst can achieve a lignin conversion of 87.62% with a 42.25% monophenol yield in the methanol and water system. With the synergistic contribution of multiple active sites of the catalyst and the mixed-solvent system (water, methanol, and 1, 4-dioxane), a remarkably high yield of 62.95% of mono-phenolic compound was achieved at 260 °C and 3 MPa N2 with a reaction time of 4 h. The selectivity of 2-methoxy-4-methylphenol and 2-methoxy-4-ethylphenol in liquid products was 40.85 and 36.42%, respectively. Vanillin, a typical product from lignin depolymerization reported in the literature, was further degraded to monophenol in this system. The outcomes also confirmed that the in situ hydrogen production system of methanol and water coupled with 1,4-dioxane facilitated the lignin depolymerization significantly.

Selective hydrodeoxygenation of guaiacol to cyclohexanol over core-shell Cox@C@Ni catalysts under mild condition

Guaiacol, a typical lignin-derived phenolic compound, can be converted to high value-added cyclohexanol through hydrodeoxygenation (HDO). In this work, a series of core-shell Cox@C@Ni catalysts were prepared via two-step hydrothermal and calcination treatments, and applied to catalyze guaiacol to cyclohexanol. Compared with Co@C catalyst, core-shell Cox@C@Ni catalysts exhibited much better catalytic performance. Almost 100% guaiacol conversion and 90% cyclohexanol selectivity were achieved over Co1.2@C@Ni catalyst at 220 °C, 0 MPa N2 for 2 h using isopropanol as H-donor solvent, which was carried out under much milder conditions compared with previous research. The structure feature of core-shell Cox@C@Ni catalysts were analyzed by BET, XRD, SEM, TEM, HRTEM, etc. The catalyst compositions and acidities played a significant role on hydrodeoxygenation of guaiacol via ICP and NH3-TPD analysis. The influences of reaction temperature, reaction time and initial nitrogen pressure were also investigated to explore the optimal reaction condition. Moreover, the possible reaction pathways and reaction mechanism was deduced based on the product distributions and physicochemical properties.

Selective catalytic ethanolysis of C-O bonds in lignite-related model compounds and Xilinguole lignite over difunctional Ni/HZSM-5 in H2-free system

Catalytic cracking of C-O bond is one of the important strategies for conversion of lignite into soluble organic matter. Ni/HZSM-5 was prepared by a modified deposition precipitation method with the Ni mass ratio ranging from 5% to 20% and evaluated by catalytic cracking benzyloxy benzene (BOB) and benzyl ether (BE). BOB was completely converted in ethanol over Ni15%/HZSM-5 under 1 MPa N2 at 240 °C for 2 h, while BE was completely converted at 180 °C. Ethanol could be activated to CH3CH2O· and H· over Ni nanoparticles supported on HZSM-5, which cleaved the C-O bond in BOB and BE. Additionally, the Ni15%/HZSM-5 was also successfully applied in catalytic ethanolysis of resides from ethanolysis Xilinguole lignite (XL) without H2 at 300 °C. The soluble portion yields from ethanolysis of XL and catalytic ethanolysis of residue are 47.8% and 15.1%, respectively. Soluble portion 1 (SP1) and catalytically soluble portion 1 (SP1C) were identified by gas chromatography/mass spectrometry. Different from SP1 mainly containing esters and phenols, SP1C is mainly composed of alkanes, arenes, and esters. In conclusion, catalytic ethanolysis of lignite in H2-free system is a potential way to cleave C-O bonds and prepare lignite-derived organic chemicals.

Low-shrinkage biodegradable PBST/PBS foams fabricated by microcellular foaming using CO2 & N2 as co-blowing agents

Poly (butylene succinate-butylene terephthalate) (PBST) displays favorable foamability with the supercritical CO2 as the blowing agent, but the foams behave serious shrinkage behavior. In this work, a serious of fully biodegradable PBST/poly (butylene succinate) (PBS) microcellular foams with low volume shrinkage ratio were fabricated with the co-blowing agent of CO2 & N2. The presence of PBS can not only improve the rheological behavior, crystallization and mechanical properties to alleviate shrinkage process, but also play the role of nucleating agent to promote cell nucleation. With the increasing content of PBS, the cell size of the foam decreases from 25.0 μm to 7.03 μm, the cell density increases from 8.84×108 to 3.19×1010 cells/cm3 and the volume shrinkage ratio reduces from 62.10% to 47.81%. Furthermore, it is demonstrated that the introduction of N2 can inhabit the shrinkage behavior of PBST/PBS foams effectively. With the introduction of 12 MPa CO2 and 8 MPa N2, the volume expansion ratio of PBST/PBS10 microcellular foam can achieve 10.6-fold with good dimensional stability.