核壳结构纳米ZnO@Au的制备、表征和光催化性能研究

以Zn(CH3COO)2·2H2O(ZnAc2)为原料,采用晶种诱导生长法制备了单分散性的球形纳米ZnO,并通过种子生长法在上面负载一层纳米Au。利用透射电镜(TEM)分析了纳米ZnO@Au的形貌、并用X射线衍射(XRD)分析了其物相组成,利用紫外-可见光谱(UV-Vis)和光致发光光谱(PL)研究了其光谱特征,以罗丹明B(RB)模型污染物,在紫外光照射下评价了纳米ZnO@Au的光催化活性。结果表明:ZnO为纤锌矿型结构,表面沉积一层金纳米微粒,形成核壳结构ZnO@Au;光催化结果显示,金沉积提高了ZnO的光催化活性。     

ZrO_2纳米微粒的制备、表征及作为MACs添加剂的摩擦学性能

制备了氧化三辛基膦表面修饰的油溶性ZrO2纳米微粒,用透射电镜(TEM)、X-射线衍射仪、红外光谱仪对其进行表征,研究了其作为多烷基环戊烷(MACs)添加剂的摩擦学性能及润滑机理.结果表明:ZrO2纳米微粒粒径大约为7～8 nm,分布比较均匀,无明显团聚,在非极性溶剂中能很好地溶解和稳定分散;作为MACs添加剂,在摩擦过程中,无机ZrO2纳米微粒以沉积膜形式沉积在摩擦副表面,有机修饰剂中的活性P元素在摩擦副表面发生了化学反应,形成了FePO4极压润滑膜,ZrO2沉积膜和FePO4极压润滑膜的协同作用起到了良好的抗磨和抗极压作用.     

纳米Cu_2O/Ag复合材料的制备、表征和抗菌活性研究

通过溶胶-凝胶法制备了单分散性的球形纳米Cu_2O,采用无还原剂的取代反应法在上面负载一层纳米Ag,制备了核壳结构的Cu_2O/Ag纳米复合材料。利用透射电镜(TEM)分析了纳米Cu_2O/Ag的形貌、并用X射线衍射测(XRD)X射线光电子能谱(XPS)分析了其物相组成,利用紫外-可见光谱(UV-Vis)和光致发光光谱(PL)研究了其光谱特征,用大肠杆菌和金黄色葡萄球菌作为测试菌研究Cu_2O/Ag抑菌性能。结果表明,Cu_2O平均直径为150nm,表面纳米Ag粒子直径为7 nm,形成核壳结构Cu_2O/Ag对大肠杆菌抑菌率为93%,对金黄色葡萄球菌为95%。     

核壳型纳米复合材料Cu Fe_(2)O_(4)@NH_(2)@Pt的制备及催化性能北大核心CSCD

采用溶剂热法制备磁性CuFe_(2)O_(4)亚微球,以三氨丙基三甲氧基硅烷(APTMS)为表面修饰剂对CuFe_(2)O_(4)进行氨基化修饰,吸附Pt^(4+)离子后用乙二醇原位还原制备CuFe_(2)O_(4)@NH_(2)@Pt复合材料。利用透射电子显微镜(TEM)、能量色散X射线光谱仪(EDX)、X射线光电子能谱分析(XPS)、X射线衍射(XRD)、紫外可见分光光度计(UV-Vis)和振动样品磁强计(VSM)对样品形貌、结构、晶型和催化性能等进行表征。以有机染料对硝基苯酚和无机染料铁氰酸钾为目标污染物研究其催化性能,结果显示6 min内,对硝基苯酚降解率约99.9%,9 min内,铁氰酸钾降解率约97%。为高效便捷的处理水污染提供了思路和方法。     

梨形核壳结构氧化锌/银亚微米球的制备、表征及光学性能

利用亚锡离子还原银离子生成的金属银沉积在合成的梨形氧化锌表面作为晶种,进一步生长银纳米粒子,制备了梨形的、核壳结构的、单分散的氧化锌/银亚微米球。利用X射线衍射、透射电镜、能量色散X射线谱、紫外可见吸收谱及光致发光谱对所制备样品的形貌、微观结构、组成和光学性能进行了表征。结果表明:(1)样品是由梨形亚微米氧化锌核和银纳米颗粒壳组成;(2)在氧化锌表面的银纳米粒子作为光激发产生的电子捕获剂提高了光产生的载流子的分离效率,在能量没有改变的情况下减少了紫外发射光的强度,淬灭了可见发射光。     

Theoretical Prediction of the Photovoltaic Properties of BFBPD-PC_(61) BM System as a Promising Organic Solar Cell

In this work,the photovoltaic properties of BFBPD-PC_(61) BM system as a promising high-performance organic solar cell(OSC) were theoretically investigated by means of quantum chemistry and molecular dynamics calculations coupled with the incoherent charge-hopping model.Moreover,the hole carrier mobility of BFBPD thin-film was also estimated with the aid of an amorphous cell including 100 BFBPD molecules.Results revealed that the BFBPD-PC_(61) BM system possesses a middle-sized open-circuit voltage of 0.70 V,large short-circuit current density of 17.26 mA ·cm~(-2),high fill factor of 0.846,and power conversion efficiency of 10%.With the Marcus model,in the BFBPD-PC_(61) BM interface,the exciton-dissociation rate,kdis,was predicted to be 2.684×10~(13) s~(-1),which is as 3~5 orders of magnitude large as the decay(radiative and non-radiative) one(10~8~10~(10)s~(-1)),indicating a high exciton-dissociation efficiency of 100% in the BFBPD-PC_(61) BM interface.Furthermore,by the molecular dynamics simulation,the hole mobility of BFBPD thin-film was predicted to be as high as 1.265 × 10~(-2) cm~2·V~(-1)·s`(-1),which can be attributed to its dense packing in solid state.     

BTBPD-PC61BM体系光伏性质的密度泛函理论计算

Designing and fabricating high-performance photovoltaic devices have remained a major challenge in organic solar cell technologies.In this work,the photovoltaic performances of BTBPD-PC₆₁BM system were theoretically investigated by means of density functional theory calculations coupled with the Marcus charge transfer model in order to seek novel photovoltaic systems.Moreover,the hole-transfer properties of BTBPD thin-film were also studied by an amorphous cell with 100 BTBPD molecules.Results revealed that the BTBPDPC₆₁BM system possessed a middle-sized open-circuit voltage of 0.70 V,large short-circuit current density of 16.874 mA/cm²,large fill factor of 0.846,and high power conversion efficiency of 10%.With the Marcus model,the charge-dissociation rate constant was predicted to be as fast as 3.079×10¹³ s^-1 in the BTBPD-PC₆₁BM interface,which was as 3-5 orders of magnitude large as the decay (radiative and non-radiative) rate constant (10⁸-10¹⁰ s^-1),indicating very high charge-dissociation efficiency (～100%) in the BTBPD-PC₆₁BM system.Furthermore,by the molecular dynamics simulation,the hole mobility for BTBPD thin-film was predicted to be as high as 3.970×10^-3 cm²V^-1s^-1,which can be attributed to its tight packing in solid state.