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化石燃料的大量开采和利用所导致的能源与环境问题是当今社会可持续发展必须面对的两大挑战. 燃料电池通过电化学反应将燃料中的化学能直接转化为电能, 是目前清洁高效的可再生能源转化装置. 光助燃料电池将光响应成分引入到燃料电池中, 可以实现光能/电能和化学能/电能的双重转化, 从而有效提高能源利用效率, 是未来能源转化装置的发展方向, 在实际应用方面具有重要意义和广阔前景. 本文对光助燃料电池进行了简要综述, 重点介绍了我们小组近些年来在该领域的相关研究进展, 总结了目前存在的一些问题, 并对其发展趋势进行了展望. 相似文献
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蓄电池是蓄积电能,以备需要时再将电能放出的仪器。如铅蓄电池及铁镍轻蓄电池。蓄电池中的变化是化学能和电能之间的反复转变。由化学能转变为电能时叫放电;由电能转变为化学能时叫充电。蓄电池在汽车,拖拉机,电话局,电灯公司,矿井,坦克,鱼雷以及潜水艇等发电装置中有着广泛的应用。 相似文献
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虽然原子能的应用近年来有了重大发展,但迄今人类各种活动中耗用的能量仍主要来自化学能。化学能可以直接转变为机械能(目前尚无高效、大功率实用装置),更多地则是采用热机来实现这种转变。除此之外,更大量的化学能是用来“发电”或通过电能这一中间形式再进一步加以利用。因此“化学能→电能”转换具有极重要的意义。 相似文献
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电动势形成机理和电极电势的含义 总被引:1,自引:0,他引:1
热力学定律应用到电化学体系,使我们能够建立电化学体系中的电能和化学能之间的定量关系。但是,作为研究宏观规律的热力学,不可能指出化学能转变为电能的机理;构成电动势值的各个部分以及电极电势的性质。 相似文献
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为配合高中新教材(鲁科版)《化学反应原理(选修)》第一章第三节“化学能转化为电能——电池”中氢氧燃料电池内容的学生阅读材料,介绍微生物燃料电池的基本构造、工作原理及产电机制,旨在帮助学生拓展知识,提高对化学的兴趣。 相似文献
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燃料电池微型实验可作为讲授“化学变化中的能量转化 :电能→化学能→电能”时的一个生动的演示实验。一些书中介绍了以下 2种实验装置[1,2 ] ,见图 1、图 2 :图 1图 2实验时 ,首先把电极接上 3V~ 6V的直流电源电解 2min左右 ,然后断开电源 ,把发光二极管接到电极上。此时刚被电解出来的H2 和O2 便分别在电极上反应而释放出电能 ,发光二极管便发光 (用H2 SO4 或KOH溶液时需 2个电池串联 ,而使用NaNO3或Na2 SO4 等溶液时只要一个燃料电池即可 )。显然这些装置较复杂 ,制作麻烦 ,装液困难 ,药品用量大 ,而且只有视觉效… 相似文献
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电化学能量转换装置包括将化学能转变为电能的各种化学电源,以及将电能转变为化学能的各种电解装置。设计这些装置时既要考虑各种能量之间的转换效率(常用%表示),又要考虑单位体积(或重量)设备中转换过程的进行 相似文献
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燃料电池(FC)是一种将贮存在燃料和氧化剂中的化学能直接转化为电能的发电装置。它的发电方式与常规的化学电源一样。电极提供电子转移的场所,阳极催化燃料(如氢等)的氧化过程,阴极催化氧化剂(如氧)的还原过程,导电离子在将阴阳极分开的电解质内迁移,电子通过外电路作功并构成总的电回路。在电池内这一化学能向电能的转化 相似文献
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A simple and economical method for molecular correlation energy calculations is developed. In this method, the internal part of the correlation energy is calculated by means of a CI in a minimal basis set and the non-internal part (semi-internal and all-external) is evaluated using an original atoms-in-molecule method. It is successfully applied to the determination of dissociation energies of some diatomic (H2, NH, C2, CN, N2, CO, NO, O2, F2) and polyatomic (H2O, N2O, CO2, N3H, CH2N2, CH2CO, C2N2) molecules. The results are compared to those obtained using very elaborate variational methods.Aspirant du Fonds National Belge de la Recherche Scientifique. 相似文献
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Sergei F. Vyboishchikov 《International journal of quantum chemistry》2008,108(4):708-718
The present work provides a technique for partitioning the atomization energy of a molecule into diatomic contributions. The method is largely based on the redistribution of the kinetic energy term in Mayer's energy partitioning and uses free‐atom energies as a reference. The comparison of Mayer's original method, the alternative Ichikawa–Yoshida approach, and the new atomization energy partitioning (AEP) shows that the new approach has advantages in describing trends in diatomic energies in molecules with triple bonds, as well as for hydrogen bonds. The proposed AEP is a viable alternative to Mayer's energy partitioning method. © 2007 Wiley Periodicals, Inc. Int. J. Quantum Chem, 2008 相似文献
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Potential energy contour curves for some simple molecules interacting with a test atom (a Li atom in the ground state) are
calculated by theab initio method. Relative hardness of the repulsive molecular surface is found to be anisotropic. This indicates that the outer boundary
surface of a molecule changes its form depending on the extent of applied external forces. The attractive nature of the molecular
surface is demonstrated to be local. Surroundings of electronegative atoms having nonbonded electron pairs are found to be
attractieve to the test atom having both electron-donating and electron-accepting abilities. 相似文献
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The interaction energy of a molecule M with a point-like charge q can be partitioned into simpler contributions, two of which can be expressed in terms of the charge distribution M of the sole M. The first term, qV(r), represents the interaction of q with the undistorted charge
M
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of M while the second q
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P(r) gives the additional contributions due to the polarization of
M
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under the influence of the charge q placed at the point r. In this paper we investigate the possibility of getting an inexpensive and sufficiently accurate analytical representation of P(r) over the whole space outside the van der Waals volume of M. 相似文献
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Ionization energy functions of triethyl amine, tri-n-propyl amine, N,N-dimethyl-benzenamine and N,N-diethyl-benzenamine, and appearance energy functions of major products of
dissociative ionization have been measured using a high sensitivity crossed electron beam-molecular beam apparatus incorporating
a quadrupole mass spectrometer and an on-line laboratory computer. The data obtained is useful in understanding the role of
dopants in gas laser plasmas. 相似文献
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Serge Crouzy Jerme Baudry Jeremy C. Smith Benoît Roux 《Journal of computational chemistry》1999,20(15):1644-1658
Accurate calculation of potential energy and free-energy profiles along reaction coordinates of biological processes such as enzymatic reactions or conformational changes is fundamental to the obtention of theoretical insight into protein function. We describe here the practical implementation of the Automatic Map Refinement Procedure (AMRP) and two-dimensional Weighted Histogram Analysis Method (WHAM) for efficient computation of adiabatic potential energy and free-energy maps, respectively. Methods for efficiently sampling configuration space with high-energy barriers and for removing hysteresis in the case of periodic reaction coordinates are presented. The application of these techniques to the isomerization of the C13C14 and C15N16 bonds in the retinal of bacteriorhodopsin is described. In dark-adapted bacteriorhodopsin (bR), the retinal moiety exists in two conformers, all-trans and (13,15)cis, with the latter making ≃67% of the population. This experimental free energy difference is reproduced here to within kBT. ©1999 John Wiley & Sons, Inc. J Comput Chem 20: 1644–1658, 1999 相似文献
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面对日益枯竭的能源危机,氢能是一种洁净、最有前景的替代能源。目前在各种制氢的方法中光催化分解水制氢的研究最多,光解水过程中催化剂最关键,本文对利用太阳能光解水的途径、提高光催化反应效率以及光催化剂的开发研究进行了综述。 相似文献
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作者使用计算机绘制了气体分子能量分布曲线图 ,较全面的阐明了活化能与温度的关系。是对无机化学中活化能与温度关系图的改进与补充。 相似文献
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太阳能光解水制氢的研究进展 总被引:48,自引:0,他引:48
本文概述了利用光催化技术催化分解水制氢的反应机理和研究进展。结合作者的最近研究,重点描述了TiO2及过渡金属氧化物,层状金属氧化物以及某些能利用可见光的光催化材料的结构和光催化特性,阐述了核课题的意义和今后的研究方向。 相似文献
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Govindasamy Vinoth Sekar Indira Madheswaran Bharathi Anandhan Durgadevi Ravikumar Abinaya Luis G. Alves Ana Margarida Martins Kuppannan Shanmuga Bharathi 《应用有机金属化学》2019,33(11)
A new class of half‐sandwich (η6‐p‐cymene) ruthenium(II) complexes supported by 2‐aminofluorene derivatives [Ru(η6‐p‐cymene)(Cl)(L)] ( L = 2‐(((9H‐fluoren‐2‐yl)imino)methyl)phenol ( L 1 ), 2‐(((9H‐fluoren‐2‐yl)imino)methyl)‐3‐methoxyphenol ( L 2 ), 1‐(((9H‐fluoren‐2‐yl)imino)methyl)naphthalene‐2‐ol ( L 3 ) and N‐((1H‐pyrrol‐2‐yl)methylene)‐9H‐fluorene‐2‐amine ( L 4 )) were synthesized. All compounds were fully characterized by analytical and spectroscopic techniques (IR, UV–Vis, NMR) and also by mass spectrometry. The solid state molecular structures of the complexes [Ru(η6‐p‐cymene)(Cl)(L2)], [Ru(η6‐p‐cymene)(Cl)(L3)] and [Ru(η6‐p‐cymene)(Cl)(L4)] revealed that the 2‐aminofluorene and p‐cymene moieties coordinate to ruthenium(II) in a three‐legged piano‐stool geometry. The synthesized complexes were used as catalysts for the dehydrogenative coupling of benzyl alcohol with a range of amines (aliphatic, aromatic and heterocyclic). The reactions were carried out under thermal heating, ultrasound and microwave assistance, using solvent or solvent free conditions, and the catalytic performance was optimized regarding the solvent, the type of base, the catalyst loading and the temperature. Moderately high to very high isolated yields were obtained using [Ru(η6‐p‐cymene)(Cl)(L4)] at 1 mol%. In general, microwave irradiation produced better yields than the other two techniques irrespective of the nature of the substituents. 相似文献