查找使用阿拉丁产品的科研文献

Exploration of microwave absorptivity and catalysis of CMF@Co-MoS2 for microwave-initiated depolymerization of lignin

Yishuai Fu,Wenliang Wang,Hui Miao,Yangyi Cui,Yutong Chen,Ziwei Wang,Guowei Xiao,Bailiang Xue,Weikun Jiang

Obtaining key platform chemicals from lignin is a sustainable refining concept of the non-petroleum route. Rapid pyrolysis is a potential refining technology, and microwave-assisted catalytic depolymerization with low energy consumption is preferred. Herein, we reported the strategy of microwave-initiated depolymerization using a self-designed dynamic vapor flow reaction system with a facilely prepared CMF@Co-MoS 2 -0.18 catalyst, achieving efficient conversion of lignin (Dealkalize) to monophenol. Under constant microwave irradiation (2.45 GHz), the CMF@Co-MoS 2 -0.18 catalyst had excellent dielectric properties (Dielectric loss factor: 0.56) and microwave heating properties (∼140 s rise to ∼ 600℃). Therefore, microwave-initiated depolymerization of lignin showed that the CMF@Co-MoS 2 -0.18 catalyst can improve the monophenol content (54.72 %) and phenol selectivity (35.84 %) under the synergistic effect of microwave absorptivity and catalysis. The reaction of the lignin model and kinetics analysis show that the CMF@Co-MoS 2 -0.18 catalyst increases the yield of monophenol by reducing depolymerization activation energy and selectively breaking the β -O-4 bond. The finite element analysis pointed out that under microwave irradiation, CMF@Co-MoS 2 -0.18 continuously conducted heat to lignin and the lignin vapor would have sufficient energy to collide with the catalyst active site at a high frequency, which led to an increase in the pre-exponential factor and initiated catalytic depolymerization lignin. In summary, we provide a potential pathway for the rapid conversion of lignin into key platform chemicals.

A 3D porous Fe-MoS2/CMF catalyst for high-efficient catalytic reforming of lignin vapor by microwave irradiation

Wenliang Wang,Jiale Huang,Yishuai Fu,Weikun Jiang,Yutong Chen,Yujun Ma,Sizhe Han

Improving the yield of target monophenols plays an important role in increasing the economic competitiveness of lignin valorization. In this study, a 3D porous Fe-MoS 2 /CMF catalyst with nanoflower microstructure was successfully fabricated by a simple one-step hydrothermal method. The catalytic depolymerization of the lignin β-O-4 model showed that Fe-doping increased the efficiency of the catalytic conversion reaction and promoted the cleavage of the β-O-4 ether bond, in agreement with theoretical calculations. Reforming of lignin depolymerization vapor revealed that the Fe-MoS 2 /CMF catalysts significantly improved the selectivity of phenol (30.01 wt%) and styrene (16.34 wt%) with the decrease of oligomers . Moreover, finite element simulation showed that the Fe-MoS 2 /CMF catalysts can also enhancing the local thermal effect by creating hot spots on the surface, thereby facilitate the lignin vapor reforming. Consequently, this work provides a promising method for the efficient production of phenol and styrene from lignin using bimetallic nanoarray microwave responsive catalyst.

rGO/CTAB/CMF Flexible Pressure Sensor Based on Honeycomb Structure for Human Posture Signal Acquisition

Yi Jiang,Limei Zhang,Junlai Jiang,Suwen Li,Yanling Cao,Jinying Yue,Hao Gu

Detecting pressure plays a vital role in electronic skin, which holds vast potential for recognizing physiological signals within the human body. Conventional pressure detection devices frequently encounter issues such as limited detection ranges and low cyclic retention rates. This study utilizes electrostatic self-assembly to precisely deposit reduced graphene oxide (rGO) onto the substrate surface, thereby creating a highly sensitive pressure feedback layer upon reduction. Furthermore, electrostatic spinning is employed to fabricate poly(vinyl alcohol) fibers at the interface between the pressure feedback layer and the interdigitated electrodes, thereby augmenting device sensitivity. Sensors fabricated using this method demonstrate exceptional sensing capabilities across a broad pressure spectrum, achieving ultrahigh sensitivities of 195.44, 165.79, and 125.95 kPa–1 within the ranges of 0–2.7, 2.7–6.91, and 6.91–20 kPa, respectively. They exhibit a rapid deformation response of 92 ms and a fast deformation recovery of 70 ms. Moreover, these sensors display outstanding durability, maintaining over 80% cyclic retention after 10,000 loading–unloading cycles. Finite element numerical simulation results suggest that the rGO/CTAB/CMF composite material, prepared using this method, exhibits superior mechanical and sensing properties. Furthermore, by integration with a custom microprocessor, the sensor’s operational capability is significantly enhanced, enabling precise processing and analysis of limb signal data in everyday situations.

Microwave synthesis of CMF@FexOy-CN: a highly dispersible magnetically recyclable photocatalyst for efficient Rh B degradation

Chengqi Feng,Anran Li,Yuxin Zhu,Yan Lei,Chenkai Jin,Juncheng Huang,Haining Na,Jin Zhu

Polluted water poses a significant threat to human health and ecological balance, necessitating the development of efficient and cost-effective water purification technologies. This study synthesized a composite photocatalytic material (CMF@Fe x O y -CN) using a microwave radiation synchrotron cooling technique. This material incorporates iron oxide-doped g-C 3 N 4 and in-situ micro-fibrillated cellulose, exhibiting high dispersion stability and magnetic recyclability. The material demonstrates a bandgap energy ( E g ) of 2.69 eV. Remarkably, 25 mg/20 mL of CMF@Fe x O y -CN (with 40 wt% Fe x O y -CN loading) achieved a 97.9 % degradation of Rhodamine B (Rh B) within 1 h. Even after 10 cycles, the degradation efficiency remained high at 89.4 %. The superoxide radical (·O 2 − ) played a critical role in Rh B degradation, facilitated by the stable dispersion of CMF. The issue of low photocatalytic efficiency, often caused by poor dispersion of photocatalysts, was addressed through the in-situ micro-fibrillation of cellulose, offering a green and economical solution. This study provides a theoretical foundation for applying photocatalysis in water purification.

Elastic Multifunctional Pressure Sensor Based on C–NiCoZn–O/CMF Composites for Polar Exploration

Hao Gu,Yi Jiang,Xijia Yang,Yue Yang,Xuesong Li,Liying Wang,Wei Lü

Flexible and wearable pressure sensors have attracted significant attention due to their wide range of potential applications. However, they often suffer from low sensitivity, narrow pressure detection range, and poor mechanical flexibility. In this work, a multifunctional 3D pressure sensor based on a ternary metal oxide@carbon-based sponge (C–NiCoZn–O/CMF) was developed by the hydrothermal method. The pressure feedback layer of the sensor was uniformly coated with C–NiCoZn–O on the surface of the framework, which improved the device’s conductivity, sensitivity, and stability significantly. The sensitivities of 41.99, 23.39, and 11.19 kPa–1 are in the ranges 0–4.01, 4.01–8.39, and 8.39–20.1 kPa, respectively, and the cyclic retention rate exceeded 90% after 2000 cycles. The C–NiCoZn–O/CMF composite demonstrated excellent electrochemical performance as an electrode for supercapacitors, with a high specific capacity of 2030 mF/cm2 at a current density of 1 mA/cm2 and a high capacity retention rate of 81.55% after 4000 cycles. As a multifunctional device, when integrated with a microprocessor, it can easily detect and process a large amount of human physiological signal data in daily work scenarios. Present composites maintain adjustable conductivity and extremely high elasticity even under extreme conditions such as liquid nitrogen and high temperatures up to 85.6 °C. This work is expected to play a great role in polar exploration, volcano survey, deep space exploration, etc.

A Wearable, Highly Sensitive Piezoresistive Pressure Sensor Based on MXene/NiMoO4@CMF and Mimicking the Hedgehog Skin Spike Structure for Its Real-Time Monitoring of Human Movement

Hong Zhang,Peihua Jin,Kaige Pang,Yi Jiang

Flexible piezoresistive pressure sensors have received much attention due to their potential for applications in personalized real-time health detection, human-computer interaction, and the Internet of Things (IoT). However, achieving a fast response and high sensitivity while keeping the cost low remains a key concern for researchers. In this paper, we simulated the spiky surface of hedgehog skin by hydrothermal growth of nickel molybdate on a carbonized sponge. Based on this, the MXene material was compounded by a process of immersion and sonication, and thus the MXene/NiMoO4@CMF (MNC) was successfully prepared. After assembly into an MNC piezoresistive pressure sensor, it shows good performance. In terms of sensitivity, the sensitivity is 31.1 kPa–1 in the pressure range of 0–10 kPa, 15.7 kPa–1 in the range of 10–15 kPa, and 3.3 kPa–1 in the range of 15–64 kPa. Moreover, it also has a fast response capability (500 ms) and excellent cyclic stability (95.7%). In addition, we integrated the MNC sensor with the ESP8266 WiFi Module IoT Development Board and an autonomously programmed UI interface. Therefore, it is capable of monitoring human health in real time and displaying abnormal statuses in the UI interface when the test value is outside the normal range. In summary, based on its high sensing performance and integrated application, the MNC sensor has a wide range of potential applications in wearable devices, IoT, and health monitoring.

Ni modified Ce(Mn, Fe)O2 cermet anode for high-performance direct carbon fuel cell

Jia Liu,Jinshuo Qiao,Hong Yuan,Jie Feng,Chao Sui,Zhenhua Wang,Wang Sun,Kening Sun

Ni modified Ce 0.6 Mn 0.3 Fe 0.1 O 2 (Ni-CMF) material is evaluated as an anode material for hybrid direct carbon fuel cell (HDCFC). The Temperature Programmed Reaction (TPR) and GC test results show that the Ni additive significantly promotes the oxidation of carbon and consequently accelerates the formation rate of CO. Moreover, the Ni-CMF material is found to show a high electrical conductivity compared to pure CMF in HDCFC operating conditions. Taking advantage of the excellent catalytic activity and high conductivity, the electrolyte-supported HDCFC with Ni-CMF anode shows a high maximum power density of 580.7   mW   cm −2 at 800   °C, when activated carbon is used as the fuel. Furthermore, the cell displays good stability under galvanostatic operation at current density of 50   mA   cm −2 at 750   °C. These results indicate that the designed Ni-CMF composite material has the potential to be developed as an alternative anode for HDCFCs.

MXene@CTAB@CMF three-dimensional elastic base for piezoresistive pressure sensors realized by electrostatic self-assembly

Yin Chunmei,Li Qinghua,Lu Zhiyi,Shi Yaochen,Lin Wei

A highly sensitive pressure-sensitive sensor based on MXene was developed using the electrostatic self-assembly method, with carbide sponges as the elastic substrate and a rational design. Specifically, CTAB was used to treat the carbide triamine sponge and conduct the electrostatic self-assembly with MXene to achieve a tightly combined conductive filler and substrate. The resulting pressure sensor showed excellent performance, with a high sensitivity of 15.05 kPa −1 under a range of 0–20 kPa, a response time of 0.1 s, and high durability under 2000 loading–unloading cycles. The minimum detection limit of the sensor was as low as 0.3 Pa, demonstrating excellent monitoring performance. Additionally, finite-element simulation analysis showed that MXene@CTAB@CMF had even better sensing performance at the same stress level. Moreover, the pressure sensor exhibited good sensing performance for various physiological signals and daily work monitoring of the human body, indicating its potential application value.

ZIF-derived carbon/BN/CMF composite PCM for enhanced latent thermal storage, photothermal conversion, and thermal insulation

Xiangfei Kong,Ruiming Nie,Jianjuan Yuan

A shape-stabilized and thermally enhanced composite phase change material based on Ag@rGO-CMF three-dimensional porous skeleton

Wenjing Chen,Lan Jiang,Xiaowu Hu

Phase change material (PCM) is a promising energy material for applications, but their inherent drawbacks, such as poor thermal conductivity and vulnerability to leakage, strongly limit their use in efficient energy storage and thermal management. To overcome these drawbacks, this paper innovatively uses a high-temperature one-step reduction method to simultaneously prepare Ag particles and reduced graphene oxide (rGO) and carbonize melamine foam (CMF) to improve thermal conductivity as well as photo-thermal conversion, and ultimately a series of shape-stable thermally conductive reinforced composite phase change material (CPCM) are prepared using vacuum impregnation. The high-density three-dimensional thermal conductivity network of Ag@rGO-CMF was able to significantly increase the thermal conductivity of CPCM (up to 104.2 % enhancement). The prepared CPCM have high loading ratios (96.9 % ~ 97.8 %), high enthalpies (154–157.7 J/g), high photo-thermal conversion efficiencies (81.3 % ~ 90.5 %), and excellent thermal management capabilities of electronic devices. This study provides a simple and feasible method for the preparation for high performance CPCM.

Reaction-extraction-reaction coupling process: The key role of intermediate product extraction during 5-chloromethylfurfural (CMF) production in the microreactor

Haodong Chu,Mengdi Li,Weichen Zhao,Qingmao Yang,Chun Shen,Tianwei Tan

Production of 5-chloromethylfurfural (CMF) from fructose conducted in two-liquid phase system has achieved a considerable CMF yield. However, correlation between extraction process and CMF yield has not been reported yet. Herein, we found quantitative relation between interfacial specific area ( a ), extraction efficiency of 5-hydroxymethylfurfural (HMF) (E HMF ),a significant precursor of CMF and selectivity of CMF (S CMF ) in the microreactor. First, we systematically investigated the impact of flow rate ratio of two phases ( F C /F D ), total fluid velocity ( u ) and residence time on S CMF and E HMF . It turned out that both F C /F D and u had a significant impact on S CMF and E HMF . In addition, both u and F C /F D had a significant impact on interfacial specific area ( a ). As u varied, we fitted and observed a linear relation between u & a (R 2 =0.994), a & E HMF (R 2 =0.997) and E HMF & S CMF (R 2 =0.999). It indicated that CMF selectivity could be controlled by HMF extraction under certain conditions. Based on these results, we proposed a strategy for obtaining high CMF productivity from fructose in the microreactor. 93.9% CMF yield (11 g/L fructose concentration) and 89.9% CMF yield (110 g/L fructose concentration) were obtained. To the best of our knowledge, this work first proposes coordination between reaction and extraction in CMF production.

Cu/Ce0.6Mn0.3Fe0.1O2-δ membrane fuel electrode fabricated by infiltration method for solid oxide electrochemical cells

Limin Liu,Yong Wang,Xiaoliang Zhou,Yixuan Yang,Chao Ma,Yuan Li,Chen Wang,Xiaohong Zhao,Bin Li

A cermet fuel electrode Cu/Ce 0.6 Mn 0.3 Fe 0.1 O 2-δ (Cu/CMF) is proposed for a reversible solid oxide electrochemical cell (SOC) with CO/CO 2 as the shuttle. Cu is inert for the carbon deposition and CMF is electrochemically active for CO oxidation and CO 2 reduction. The electrode polarization resistances in CO at 700, 750 and 800   °C are 0.328, 0.207 and 0.155   Ω cm 2 , respectively, presenting high electrochemical activity towards CO oxidation. The maximal power densities can reach up to 303.3, 482.2 and 691.9   mW/cm 2 at 700, 750 and 800   °C, respectively. When the reversible SOCs are operated in solid oxide electrolysis cell mode, the polarization resistance of the electrolysis cell for pure CO 2 reduction at 800   °C has the minimal value of 0.126   Ω cm 2 at 1.8   V. At 2.0   V, the current densities can reach up to 0.584 1.219 and 2.204   A/cm 2 at 700, 750 and 800   °C, respectively. The durability of the cell in CO for as long as 200   h indicates the electrode has remarkable stability. And the short-term stability characteristics for CO 2 electrolysis at different voltages illustrate that the cell performs well below 2.0   V. The harsh reducing environment at 2.0   V may be detrimental to the Cu/CMF electrode.