二硫化钼纳米微粒及其单层悬浮液的制备

利用硫化铵与钼酸钠为原料,制备出非晶态三硫化钼微粒,在氢气氛下煅烧晶化该非晶态三硫化钼,得到30-50nm的片状二硫化钼微粒.将制备的纳米二硫化钼微粒与正丁基锂的正己烷溶液反应48小时,然后将固体产物浸入水中,在超声分散下获得了稳定的纳米二硫化钼悬浮液,最后用XRD、TEM及HRTEM对产物进行了表征.     

A Bio‐Inspired and Biomass‐Derived Healable Photochromic Material Induced by Hierarchical Structural Design

Utilization of bionics to develop stimuli responsive polymers that can heal damage with excellent restorability is particularly attractive for a sustainable society. Herein, inspired by chameleons, a hierarchical structural design strategy is proposed and illustrated to fabricate a healable photochromic material based on a self‐healable polymeric matrix and a finely dispersed photochromic spirooxazine. The self‐healable polymeric matrix is fabricated via the integration of multiple hydrogen bonds (H bonds) and covalent cross‐links into a biomass‐derived elastomer. The dynamic nature and soft characteristics enable the as‐prepared elastomer superior extensibility as well as self‐healing ability, while the covalent cross‐links can assist the reassociation of ruptured H bonds. The representative elastomer exhibits an extensibility of 2600% and toughness of 42.76 MJ m^?3. Furthermore, it shows good self‐healing ability with complete recovery of scratch as well as restoration against 1900% of elongation and 24.1 MJ m^?3 of toughness after healing at 60 °C for 24 h. This combination of moderate toughness, good self‐healing ability, and smart photochromic property in biomass‐derived materials should largely improve their applicability, reliability, and sustainability in various materials and devices.     

二硫化钼纳米片用于修饰微生物燃料电池阳极的研究

利用简单的一步水热法制备了MoS2纳米片并用于修饰不锈钢纤维毡阳极(MoS2-SSFF),与未修饰不锈钢纤维毡阳极(SSFF)和多壁碳纳米管修饰阳极(CNT-SSFF)进行了对比研究。装配MFC运行的测试结果表明,MoS2-SSFF/MFC的功率密度为714 m W/m2,略高于CNT-SSFF/MFC的功率密度693 m W/m2,远高于未修饰SSFF/MFC的功率密度197 m W/m2。利用扫描电子显微镜(SEM)观察到MoS2纳米片呈簇状附着于MoS2-SSFF电极表面,显著增加了电极的比表面积。MoS2纳米片修饰改善了SSFF阳极的生物相容性,修饰电极在循环伏安测试(CV)中表现出良好的氧化还原性能。水热法制备的MoS2纳米片用于修饰阳极是一种高效、经济、简单的阳极修饰方法。     

Facile synthesis of MoS2/N-doped macro-mesoporous carbon hybrid as efficient electrocatalyst for hydrogen evolution reaction

A novel three-dimensional (3D) hybrid consisting of molybdenum disulfide nanosheets (MoS₂) uniformly bound at N-doped macro-mesoporous carbon (N-MMC) surface was fabricated by the solvothermal method. The resulting MoS₂/N-MMC hybrid possesses few-layer MoS₂ nanosheets structure with abundant edges of MoS₂ exposed as active sites for hydrogen evolution reaction (HER), in sharp contrast to large aggregated MoS₂ nanoflowers without N-MMC. The high electric conductivity of N-MMC and an abundance of exposed edges on the MoS₂ nanosheets make the hybrid excellent electrocatalytic performance with a low onset potential of 98 mV, a small Tafel slope of 52 mV/decade, and a current density of 10 mA cm^?2 at the overpotential of 150 mV. Moreover, the MoS₂/N-MMC hybrid exhibits outstanding electrochemical stability and structural integrity owing to the strong bonding between MoS₂ nanosheets and N-MMC.     

Electrochemical evaluation of molybdenum disulfide as a catalyst for hydrogen evolution in microbial electrolysis cells

There is great interest in hydrogen evolution in bioelectrochemical systems, such as microbial electrolysis cells (MECs), but these systems require non-optimal near-neutral pH conditions and the use of low-cost, non-precious metal catalysts. Here we show that molybdenum disulfide (MoS₂) composite cathodes have electrochemical performance superior to stainless steel (SS) (currently the most promising low-cost, non-precious metal MEC catalyst) or Pt-based cathodes in phosphate or perchlorate electrolytes, yet they cost ∼4.5 times less than Pt-based composite cathodes. At current densities typical of many MECs (2-5 A/m²), the optimal surface density with MoS₂ particles on carbon cloth was 25 g/m², achieving 31 mV less hydrogen evolution overpotential than similarly constructed Pt cathodes in galvanostatic tests with a phosphate buffer. At higher current densities (8-10 A/m²) the MoS₂ catalyst had 82 mV less hydrogen evolution overpotential than the Pt-based catalyst. MoS₂ composite cathodes performed similarly to Pt cathodes in terms of current densities, hydrogen production rates and COD removal over several batch cycles in MEC reactors. These results show that MoS₂ can be used to substantially reduce the cost of cathodes used in MECs for hydrogen gas production.     

用密度泛函方法研究N-甲基吡咯烷酮与二硫化碳的反应

N-甲基吡咯烷酮（NMP）和二硫化碳（CS₂）在加压下发生热反应生成N-甲基吡咯烷-2-硫酮.用密度泛函方法确定了该反应有两条平行的路径,获得了相关的4个过渡态和2个中间体的构型;在拟定了两步反应机理的基础上,确认了第一步反应为速度控制步骤,计算了在298K和500K下两种反应路径的活化能和速率常数.根据计算结果判断NMP羰基的α氢原子通过与羰基氧的分子内相互作用在反应中起重要作用,同时确认了反应区域为NMP的羰基碳和氧、α位上的碳和氢,以及CS₂中的碳原子和其中的一个硫原子所构成的两个并联的四元环.     

神府煤二硫化碳萃取物的组成分析

用二硫化碳萃取神府煤、用GC/MS分析萃取物,考察了萃取物的组成结构特征和部分组分的可能来源。结果表明:萃取物中的可检测成分为脂肪烃、烃基取代的芳烃和含杂原子的有机化合物,其中脂肪烃含量占绝对优势,且以7种C15-二环倍半萜烯同分异构体为主,检测出的链烃包括C18~C29正构烷烃和两种异构烷烃,烃基取代的芳烃中的芳环包括苯、萘和菲环,含杂原子有机化合物都含氧原子。     

多肽间非共价作用的质谱研究

为了研究多肽间的非共价作用,将多肽按摩尔比1:1混合,待平衡后用电喷雾电离质谱分析多肽间的相互作用.结果表明,其中部分五肽相互作用未形成非共价复合物,也有部分五肽相互作用容易形成非共价复合物,通过改变五肽的氨基酸序列和加长肽链后,用电喷雾电离质谱分析多肽间作用的变化,研究巯基、氢键和疏水作用对多肽非共价作用的影响.五肽...     

纳米二硫化钼在聚-α-烯烃润滑脂中的摩擦学性能

利用MQ - 800型四球摩擦磨损试验机考察了纳米二硫化钼和微米二硫化钼在聚-α-烯烃润滑脂中的摩擦学性能.结果表明纳米二硫化钼的减摩抗磨性能优于微米二硫化钼.这是因为纳米二硫化钼在摩擦表面形成了吸附膜,提高了润滑脂的减摩抗磨性能.     

受阻酚/丁腈橡胶复合材料的结构与性能

在丁腈橡胶中添加受阻酚AO-60制备受阻酚/丁腈橡胶复合材料。利用差示扫描量热(DSC)、 扫描电镜(SEM)、 X射线衍射(XRD)、 动态力学分析(DMTA)等测试手段对该复合材料的结构进行了表征, 并对其动态力学性能进行了研究。结果表明: 该复合材料中受阻酚AO-60的结晶性能发生变化, 由结晶态转变为无定形态。AO-60在丁腈橡胶基体中形成了富集区, 在AO-60分子间和AO-60与NBR分子之间形成了大量的氢键。该复合材料不仅存在丁腈橡胶的玻璃化转变, 还有两次异常的松弛过程, 这归因于体系中分子间氢键的解离。该复合材料具有很高的损耗性能, 有很好的阻尼材料应用前景。