Efficient ORR catalysts for zinc-air battery: Biomass-derived ultra-stable Co nanoparticles wrapped with graphitic layers via optimizing electron transfer

The poor stability of non-noble metal catalysts in oxygen reduction reaction(ORR) is a main bottleneck that limits their big-scale application in metal-air batteries. Herein, we construct a chainmail catalyst(Co-NC-AD) with outstanding stability, via the competitive complexation and post absorption strategy,consisting of highly graphitic layers wrapped uniform-size Co nanoparticles(Co-NPs). Experiments combined with density functional theory(DFT) calculations jointly confirmed that the electron ...     

Heterostructured Pd/PdO nanowires for selective and efficient CO2 electroreduction to CO

Palladium(Pd) nanostructures are highly promising electrocatalysts for the carbon dioxide electrochemical reduction(CO₂ ER). At present, it is still challenge for the synthesis of Pd nanostructures with high activity, selectivity and stability. In this work, a facile PdII-complex pyrolysis method is applied to synthesize the high-quality one-dimensional heterostructured Pd/Pd O nanowires(Pd/Pd O H-NWs).The as-prepared Pd/Pd O H-NWs have a large electrochemically active surface area, a...     

Cu-substitution P2-Na0.66Mn1-xCuxO2 sodium-ion cathode with enhanced interlayer stability

P2-type Mn-based layered oxides are viewed as promising cathode materials for sodium ion battery by virtue of their high theoretical capacity. Considering that pure Na_2/3MnO₂ suffers from poor cycling performances, Cu-substitution strategy is proposed to effectively alleviate this issue. However, the structural evolution mechanism of the Cu-containing samples still remains unclear. Herein, we propose that CuSubstitution P2-type Na_0.66Mn_1-xCu_x     

“Coffee ring” controlment in spray prepared >19% efficiency Cs0.19FA0.81PbI2.5Br0.5 perovskite solar cells

Achieving high-quality perovskite films with uniform morphology and homogeneous crystallinity is challenging owing to the coffee ring effect(CRE) in the spray-coating technologies. In this study, an evaporation/spray-coating two-step deposition method is used to fabricate Cs_0.19FA_0.81PbI_2.5Br_0.5 light harvesters for perovskite solar cells(PSCs). Considering the solid–liquid reaction, we establish a reaction-dependent regulating strategy that inhibits C...     

自动显微注射过程中图像分割的实现

自动显微细胞注射能克服人工注射时间长,易疲劳的缺点,为解决卵胞浆内自动单精子注射过程中细胞和针尖定位问题,通过基于YOLOv3神经网络和水平集相结合的方法,分割卵细胞和注射针,进而定位注射针的针尖.对比实验证明了方法能够解决传统水平集难以分割细胞和注射针的问题,完整分割出显微注射过程中发生形变的细胞,以及实现细胞内针尖...     

快速响应高压电源在KTP晶体极化反转中的应用研究

分析了KTP晶体电导率的特性,设计与研制出一种新型的高压脉冲放大器,可将任意信号发生器产生的信号线性放大,响应速度快,最高输出电压为4000V,最大输出电流为30mA,功率可达100W.用其在KTP晶体上进行多次极化反转实验,取得良好的实验结果.     

凝胶改性基底微藻细胞黏附特性及热力学分析

为强化微藻生物膜成膜过程中藻细胞与基底黏附,同时解决藻细胞残留造成的基底重复利用性差的问题,用聚N-异丙基丙烯酰胺(PNIPAAm)温缩型凝胶修饰基底.傅里叶红外光谱分析改性表面化学特性;结合微藻培养温度给出适宜藻细胞黏附的基底浸润特性;通过构建热力学模型,明晰温度对藻细胞与温缩型凝胶改性基底界面作用自由能的影响规律,...     

A-site cation engineering enables oriented Ruddlesden-Popper perovskites towards efficient solar cells

Quasi two-dimensional(Q-2D) perovskites with favorable environment stability and satisfied device performance are attracting great attention and becoming star materials.The unique characteristics of more wide range of Goldschmidt tolerance factor endow Q-2D perovskites with exceptional composition tunability and great potential.Herein,Guanidinium(Gua) was firstly introduced into the octahedral cation site of BA₂MA₃Pb₄I₁₃ perovskite to partially replace...     

White-light-driven fluorescence switch for super-resolution imaging guided photodynamic and photoacid therapy

Photocaged fluorophores with photoactivatable characteristics presented important applications in imaging the biological structures and processes.Taking advantage of their super-resolution imaging merits to manipulate and visualize anti-cancer treatment is always a goal of modern clinical medicine.Traditional photodynamic therapy(PDT) is a noninvasive treatment but limited in intracellular oxygen content.Type I PDT and photoacid therapy(PAT) are two effective supplements of traditional PDT espec...     

18.01% Efficiency organic solar cell and 2.53% light utilization efficiency semitransparent organic solar cell enabled by optimizing PM6:Y6 active layer morphology

Optimizing the photoactive layer morphology is a simple, promising way to improve the power conversion efficiencies(PCEs)of organic solar cells(OSCs). Here, we compared different post-processing treatments on PM6:Y6 blend films and relevant effects on device performances, including as-cast, thermal annealing and solvent annealing. This solvent annealing processes can effectively improve the vertical distribution and aggregation of polymer donors and small molecule acceptors, then optimize the ac...