氧化石墨烯/磺化聚苯并咪唑高温质子交换膜的制备和表征

通过共混法和原位聚合法成功制备氧化石墨烯（GO）/磺化聚苯并咪唑（SPBI）质子交换复合膜。用FTIR及TEM表征了复合膜的结构,并测试了复合膜的热稳定性、力学性能、尺寸稳定性、含水率、酸掺杂率、氧化稳定性及质子电导率,重点考察不同制备方法、GO的加入对GO/SPBI质子交换复合膜结构和性能的影响。实验结果表明,GO在Y-GO/SPBI-1%复合膜中呈薄片状并良好分散。添加GO后复合膜的力学性能大幅提高,拉伸强度相较于Nafion 117膜（26.65MPa）提高了2.5倍。Y-GO/SPBI-1%复合膜热稳定性稍高于G-GO/SPBI-1%复合膜。Y-GO/SPBI-1%复合膜拥有与SPBI膜相当的含水率,比G-GO/SPBI-1%复合膜的含水率提高了51.36%,表明原位聚合法制备的膜具有良好的保水能力。原位聚合法制备的复合膜具有更高的酸掺杂率和更低的酸溶胀度,提高了膜的尺寸稳定性。Y-GO/SPBI-1%质子交换复合膜在相对湿度40%、160℃下具有最高的质子电导率0.113S/cm。GO上的含氧官能团有助于复合膜中质子的跳跃,原位聚合法使GO更均匀地分散在SPBI基质中,对复合膜质子电导率的提高起到关键作用。     

燃料电池用纳米改性聚苯并咪唑阴离子交换膜的制备

以环氧氯丙烷和1–甲基咪唑为原料制备新型离子液体(IL),以IL为原料对氧化石墨烯(GO)进行表面修饰制备离子液体功能化氧化石墨烯(IL–GO),以IL–GO为添加剂制备基于含氟聚苯并咪唑(FPBI)复合膜。研究了IL–GO的含量对复合膜的热稳定性、力学强度、离子电导率、离子交换容量(IEC)、吸水率、溶胀度和耐碱性等性能的影响。研究结果表明,复合膜的IEC、离子电导率和拉伸性能都随着IL–GO含量的增加而增大,当IL–GO含量为30%时其拉伸应力和拉伸弹性模量分别达到77.5 MPa和1.95 GPa,在80℃下,其最大离子电导率可达72.3 m S/cm,然而复合膜的热稳定性并没随着IL–GO含量的增加而改变。FPBI/IL–GO复合膜具有良好的稳定性,该系列阴离子交换膜有望在碱性阴离子交换膜燃料电池中得到应用。     

环氧改性氧化石墨烯/水性聚氨酯复合膜的制备及其增强作用

采用环氧氯丙烷（EPI）对氧化石墨烯（GO）进行共价键改性制备环氧改性氧化石墨烯（EPGO）,再将EPGO共混水性聚氨酯（WPU）制得含有不同EPGO质量分数（以水性聚氨酯有效含量计）EPGO/WPU复合膜,通过FT-IR、XRD、TEM表征了EPGO的结构和形态并测试了成膜拉伸性能、耐磨性能。实验结果表明：EPGO的添加可以明显提高水性聚氨酯膜的拉伸强度,当添加0.8wt%的EPGO时,复合膜的拉伸强度达到12.9MPa,较空白膜提高了67.5%,杨氏模量提高了39.2%,且复合膜的耐磨性显著提高,表明EPGO的添加对水性聚氨酯膜有一定的增强作用。     

磺酸修饰的金刚石掺杂磺化聚芳醚砜质子交换膜的制备与性能

利用KMnO₄、浓H₂SO₄的氧化性及纳米金刚石边缘缺陷引入含氧官能团,得到氧化金刚石（OND）。OND在强碱条件下与1,4-丁磺酸内酯反应,进行烷基磺酸的接枝,制备带有磺酸烷基链的纳米金刚石（SND）。热重分析、红外光谱结果表明了烷基磺酸基团的成功引入,SND的离子交换容量（IEC）达到1.1mmol/g。SND与磺化聚芳醚砜（SPAES）共混后,通过溶液浇铸法制备了表面均匀平整的SPAES-SND复合膜。SPAES-SND复合膜具有较高的吸水率及较低的溶胀率、更高的氧化稳定性及电导率。其中,SPAES-SND-0.5在80℃时最高吸水率达到了75%,拉伸强度为31.3MPa,断裂伸长率为25.1%,在80℃水中的质子电导率达到166mS/cm,显示了良好的综合性能。SPAES-SND-0.5膜在80℃、100%相对湿度（RH）下燃料电池最大功率密度达到了527mW/cm²,相比于原始的SPAES膜（347mW/cm²）提高了51.9%,其优异的质子电导率和电池功率表现出较好的应用前景。     

三羧基丁烷膦酸锆/SPPEK复合膜在高温不同湿度下电导率

磺化杂萘联苯聚醚酮（SPPEK）膜在温度高于100℃时会因严重失水而导致电导率急剧下降。为此，合成出具有较高电导率的吸湿性质子导体1，2，4-三羧基丁烷-2-膦酸锆［Zr（PBTC）］，并将其掺杂到SPPEK中制备出Zr（PBTC）/SPPEK复合膜。实验表明，Zr（PBTC）的掺杂能有效提高复合膜在高温低湿情况下的吸水能力，从而提高其电导率。SPPEK膜在120℃、相对湿度为40％情况下电导率仅有约10^-4 S·cm^-1，而相同条件下30% Zr（PBTC）/SPPEK复合膜的电导率达到2×10^-3 S·cm^-1。而且相对湿度越小，复合膜电导率的提高幅度越大，在相对湿度小于20%时，复合膜的电导率大约比SPPEK膜高两个数量级。     

磺化含酚酞侧基聚芳醚酮/氧化石墨烯复合质子交换膜的性能

采用共混制备了一系列磺化含酚酞侧基聚芳醚酮(SPEK-C)/氧化石墨烯(GO)复合质子交换膜,系统地研究了GO含量对复合膜性能的影响。结果表明,GO含量对膜的离子交换容量、稳定性、质子电导率和甲醇渗透率等有重要影响。复合膜质子电导率随GO含量增加而提高,GO含量为2%和5%的复合膜在80℃下质子电导率均在10^-1 S·cm^-1以上。80℃下,GO含量为5%的复合膜甲醇渗透率为6.69×10^-7 cm²·s^-1,低于同温度下复合前SPEK-C膜1个数量级。复合后膜的化学稳定性增强,离子交换容量和含水率均有提高,相对选择性明显增大,最高达SPEK-C的18.2倍。     

基于含氟聚苯并咪唑/磺化壳聚糖复合质子交换膜的制备与表征

通过磺化反应在壳聚糖(CS)上引入磺酸基团制得具备良好质子传导能力的磺化壳聚糖(SPCS)。以含氟聚苯并咪唑(FPBI)为基体材料,通过掺杂磺化壳聚糖制备得到FPBI-SPCS复合质子交换膜。研究了SPCS的质量分数对复合膜的机械性能、热稳定性、吸水率、溶胀度、质子电导率等性能影响。结果表明,复合膜的质子电导率随着SPCS质量分数的增加而增加,但是吸水率、溶胀度却随着SPCS质量分数的增加而下降,复合膜依然能够保持良好的机械性能和热稳定性。FPBI-SPCS复合膜在80℃下最高电导率达18.52 m S/cm,有望在质子交换膜燃料电池中得到应用。     

基于MIS改性的WPU/GO纳米复合乳液的研究

以2-氨基-4-羟基-6-甲基嘧啶(MIS)为改性剂,通过1-乙基-(3-二甲基氨基丙基)碳二亚胺盐酸盐(EDC·HCL)活化羧基制得MIS改性氧化石墨烯(MGO)分散液;并在水性聚氨酯乳化过程中引入MGO分散液制备水性聚氨酯/MIS改性氧化石墨烯(WPU/MGO)纳米复合乳液。通过红外光谱、热重分析、纳米粒度分析、扫描电子显微镜和力学分析对MGO,复合乳液和复合膜的结构与性能进行了表征。结果表明,当MGO的添加量为1%时,MGO在水性聚氨酯中均匀分散,纳米复合膜的杨氏模量、拉伸强度、断裂伸长率和热稳定性均有明显提高。     

BaCe_(0.8)Al_(0.2)O_3掺杂的SPEEK复合质子交换膜制备与性能

针对普通磺化聚醚醚酮(SPEEK)膜质子传导率较低的问题,提出无机掺杂的改善方法。采用共沉淀法制备BaCe_(0.8)Al_(0.2)O_3复合氧化物,将其掺杂到SPEEK膜基体中,并通过溶液浇铸法制得了SPEEK/BaCe_(0.8)Al_(0.2)O_3复合质子交换膜。对复合膜的尺寸稳定性、氧化稳定性、力学性能、质子传导率及微观形貌等进行了测试与表征。结果表明,BaCe_(0.8)Al_(0.2)O_3的掺杂可有效地提高复合膜的质子传导率。其中,SPEEK-BaCe_(0.8)Al_(0.2)O_3-9复合膜的质子传导率在80℃下达到0.187 S×cm~(-1),拉伸强度达29.43 MPa,单电池最大功率密度达0.82 W×cm~(-2),几乎可与普通的Nafion质子交换膜媲美。此外,掺杂还改善了复合膜的化学稳定性。     

直接甲醇燃料电池用三羧基丁烷膦酸锆/磺化杂萘联苯聚醚酮复合质子交换膜

用高磺化度的磺化杂萘联苯聚醚酮（SPPEK）制备DMFC质子交换膜时,膜的机械强度会因过度溶胀而下降。通过在SPPEK（DS=61%）中掺杂1,2,4-三羧基丁烷-2-膦酸锆(Zr(PBTC)),我们制备出 Zr(PBTC)/SPPEK复合质子交换膜。实验表明, Zr(PBTC)的掺杂能有效降低膜的吸水量（溶胀）,并能减小膜的甲醇透过系数。80℃时,30wt.%Zr(PBTC) /SPPEK复合膜的吸水量与SPPEK膜比降低了30％。室温下复合膜的甲醇透过系数在10－7 cm2.s-1数量级上,比Nafion 115膜低一个数量级以上。液体甲醇溶液进料的DMFC单电池测试表明,30wt.%Zr(PBTC) /SPPEK复合膜的电池性能优于SPPEK的电池性能。     

A novel polybenzimidazole composite modified by sulfonated graphene oxide for high temperature proton exchange membrane fuel cells in anhydrous atmosphere

A novel functional graphene with high ion exchange capacity (IEC) was prepared by grafting reaction induced by ⁶⁰Co γ‐ray irradiation using graphene oxide. Then, polybenzimidazole/radiation grafting graphene oxide (PBI/RGO) composite membranes were prepared by the solution‐casting method and doped with phosphoric acid (PA) to improve their proton conductivity. The properties of PBI/GO/PA and PBI/RGO/PA membranes including the PA doping level, chemical stability, proton conductivity and mechanical properties were evaluated and compared. The tensile strength of PBI/RGO/PA membranes (ranging from 27.3 to 38.5 MPa) increases at first and then decreases with the increase of the RGO content, and is significantly higher than that of other PA doped PBI‐based membranes. The proton conductivity of PBI/RGO‐3/PA membrane is 28.0 mS cm^?1 at 170 °C without humidity, with an increase of 72.0% compared with that of PBI/PA membrane. These results suggest that PBI/RGO/PA membranes have the potential to be used as high‐temperature proton exchange membranes. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44986.     

Sulfonated poly(ether sulfone)/phosphotungstic acid/attapulgite composite membranes for direct methanol fuel cells

Novel composite sulfonated poly(ether sulfone)(SPES)/phosphotungstic acid (PWA)/attapulgite (AT) membranes were investigated for direct methanol fuel cells (DMFCs). Physical–chemical properties of the composite membranes were characterized by FTIR, DSC, TGA, SEM‐EDX, water uptake, tensile test, proton conductivity, and methanol permeability. Compared with a pure SPES membrane, PWA, and AT doping in the membrane led to a higher thermal stability and glass transition temperature (T_g) as revealed by TGA and DSC. Tensile test indicated that lower AT content (3%) in the composite can significantly increase the tensile strength, while higher AT loading demonstrated a smaller contribution on strength. Proper PWA and AT loadings in the composite membranes can increase the proton conductivity and lower the methanol cross‐over. The proton conductivity of the SPES‐P‐A 10% composite membrane reached 60% of the Nafion 112 membrane conductivity at room temperature while the methanol permeability was only one‐fourth of that of Nafion 112 membrane. This excellent performances of SPES/PWA/AT composite membranes could indicate a potential feasibility as a promising electrolyte for DMFC. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

磺化聚苯并咪唑/二氧化硅杂化质子交换膜的制备及性能

为改善磺化聚苯并咪唑的综合性能,用异氰酸丙基三乙氧基硅烷作为偶联剂,正硅酸乙酯作为前驱体,在膜内生成有机-无机杂化交联网络,制备了燃料电池用高温质子交换膜。利用傅里叶转变红外光谱（FTIR）表征了聚合物膜的化学结构。用扫描电镜(SEM)观察了聚合物膜的断面形貌。利用交流阻抗（EIS）测定了聚合物膜在磷酸掺杂后的质子传导率。研究结果表明,硅烷偶联剂的加入使得界面相容性良好。由于存在有机-无机交联结构,在膜的溶胀增加不大的前提下,磷酸掺杂量得到了增加,相应地增加了聚合物膜的质子传导率。     

聚偏氟乙烯/类基体基团修饰石墨烯导热复合材料研究

采用含类基体基团的乙烯基三甲氧基硅烷修饰氧化石墨烯(GO),再用"一锅法"将其还原得到功能化石墨烯(F-GE),通过溶剂浇注法制备出界面性能优良的聚偏氟乙烯导热复合材料(PVDF/F-GE).利用红外光谱仪(FTIR)、扫描电子显微镜(SEM)、热导率测试仪、电子拉力试验机对复合材料的改性状态、微观形貌、导热性能和力学...     

聚乳酸基纳米纤维素/石墨烯导电复合膜的制备与表征

利用真空抽滤方法,制备了纳米纤维素/石墨烯导电膜,将其嵌在聚乳酸表面得到聚乳酸基纳米纤维素/石墨烯导电复合膜。傅里叶红外（FT-IR）表征结果表明石墨烯与纳米纤维素之间存在一定的相互作用;当纳米纤维素与石墨烯质量比为1：2时,导电复合膜的电导率为12 S·cm^-1,抗张强度达到13.62 MPa,水接触角为80.6°。热重分析（TGA）表征结果表明导电复合膜有良好的热稳定性,300℃时不同质量比的导电复合膜的失重量低于10%,相比纳米纤维素,在相同温度下失重量减少了20%。以聚乳酸材料为基体的导电复合膜,其抗张强度比未被嵌聚乳酸基体的纳米纤维素/石墨烯导电膜提高15～23倍,将聚乳酸基纳米纤维素/石墨烯导电复合膜埋在土壤中5周后,质量损失了3.7%。聚乳酸材料优异的力学性能和可降解性,扩展了纳米纤维素/石墨烯导电复合膜的应用范围。制备的导电复合膜在柔性导电材料领域有潜在的应用前景。     

Preparation and properties of chitosan/acidified attapulgite composite proton exchange membranes for fuel cell applications

A composite proton exchange membrane chitosan (CS)/attapulgite (ATP) was prepared with the organic–inorganic compounding of ATP and CS. The composite membranes were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), and fourier transform infrared spectroscopy (FTIR). The mechanical properties, thermal stability, water uptake, and proton conductivity of the composite membranes were fully investigated. The composite membranes exhibited an enhanced mechanical property, dimensional and thermal stability compared to CS membrane, owing to the interface interaction between ATP and CS. The maximum tensile strength of 53.1 MPa and decomposition temperature of 223.4°C was obtained, respectively. More importantly, the proton conductivity of the composite membrane is also enhanced, the composite membrane with 4 wt% ATP content (CS/ATP-4) exhibited the highest proton conductivity of 26.2 mS cm⁻¹ at 80°C with 100% relative humidity, which is 25.1% higher than pure CS membrane. These results may explore a simple and green strategy to prepare CS-based PEMs, which have a great potential in the application of proton exchange membrane fuel cells.     

Preparation and proton conductivity of composite membranes based on sulfonated poly(phenylene oxide) and benzimidazole

The Brønsted acid–base composite membrane was prepared by entrapping benzimidazole in sulfonated poly(phenylene oxide) by tuning the doping ratios. Their thermal stability, dynamic mechanical properties and proton conductivity were investigated under the conditions for intermediate temperature proton exchange membrane (PEM) fuel cell operation. In addition, investigation of activation energies of the SPPO–xBnIm at different relative humidity was also performed. TG–DTA curves reveal these SPPO–xBnIm composite materials had the high thermal stability. The proton conductivity of SPPO–xBnIm composite material increased with the temperature, and the highest proton conductivity of SPPO–xBnIm composite materials was found to be 8.93 × 10⁻⁴ S/cm at 200 °C under 35% relative humidity (RH) with a “doping rate” where x = 2. The SPPO–2BnIm composite membrane show higher storage moduli and loss moduli than SPPO. Tests in a hydrogen–air laboratory cell demonstrate the applicability of SPPO–2BnIm in PEMFCs at intermediate temperature under non-humidified conditions.