Tian Zhongqun

Some thoughts about controllable assembly (I) — From catalysis to cassemblysis

Molecular assembly processes are in general much more complex than chemical synthesis. Their goal is the same, that to create a variety of new matter and new functional materials. In accordance with their similarities, the concept of catalysis, which is widely used in chemical synthesis, could be extended to assembly. Herein we suggest that the term “cassemblysis” be used when referring to increased rates and control during assembly. The role played by a cassemblyst in molecular assembly is similar to that played by a catalyst in a synthesis with high efficiency and selectivity. Furthermore, it may be helpful to classify some terms which are used often but without clarity in the literature, such as self-assembly and assisted self-assembly. Molecular assembly can be divided into two major types, self-assembly and assisted assembly. Most assembly processes belong to assisted assembly, which can be further divided into three categories: cassemblysis, co-assembly and field-assisted assembly. Of these three, cassemblysis is the most efficient way to create new materials (e.g., soft matter) above the molecular level. After cassemblysis, some assembly systems undergo a chemical coupling reaction which significantly enhances stability and prevents them from de-assembling. This increased stability is essential for practical applications. We call this cassembly-reaction process “catassemblysis”. We present some typical examples involving small molecules and large biological molecules to show that cassemblysis and catassemblysis are very common, especially in biological systems. We believe that photo-electro-cassemblysis is possible and that the concept of cassembly could be extended to controllable nanoparticle (or other nanostructure) assembly. Finally we discuss the primary mechanism of cassemblysis and catassemblysis. With emphasis on the experimental and theoretical methodologies of cassemblysis, controllable assembly could play a greater role in creating new matter and new functional materials.

Electrocatalytic Oxidation of Formic Acid on Pt-Se Hollow Nanosphere Modified Glassy Carbon Electrodes

National Natural Science Foundation of China [20663002]; Foundation of State Key Laboratory of Physical Chemistry of Solid Surfaces, Xiamen University, China [200511]

Reaction of p-Chloronitrobenzene Adsorbed on Silver Nanoparticles

National Natural Science Foundation of China [20973143, 91027009, 21021002]; National Key Basic Research Program of China (973) [2009CB930703]; Xiamen University, China [2010121020]

In-situ surface-enhanced Raman spectroscopic investigation on ethanol electrooxidation in different media

Electrochemical voltametric methods and in-situ electrochemical surface-enhanced Raman spectroscopy (SERS)were used to investigate the electrooxidation behavior of ethanol in different media on a roughened platinum electrode.It was found that ethanol could dissociate spontaneously to produce strongly adsorbed intermediate,CO,in acidic,neutral,and alkaline media on the roughened platinum electrode.The complete oxidation potential of CO_(ad) on the roughened platinum electrode was negatively shifted about 0.300 V in the alkaline medium(0.20 V)compared with that in the acidic and neutral media(0.50 V).The positive oxidation peak potential of ethanol was negatively shifted about 0.85 V in the alkaline medium(-0.20 V)than that in the acidic medium(0.65 V).By comparing the oxidation current and the peak potential,it was found that the electrocatalytic activity of roughened platinum electrode for ethanol and CO oxidation in the alkaline medium was higher than in acidic and neutral media.The results suggested that ethanol was oxidized to CO_2 on the roughened platinum electrode via parallel reaction mechanism in acidic, neutral or alkaline media.

Initial Behavior of the Electroless Nickel Deposition on Pretreated Aluminum

National Natural Science Foundation of China [20873114, 20833005, 21021002]; National Key Basic Research Program of China (973) [2009CB930703]; Science and Technology Project of Fujian Province, China [2009H4020]

Vibrational Spectroscopy Criteria to Determine alpha-Pyridyl Adsorbed on Transition Metal Surfaces

National Natural Science Foundation of China[20973143, 91027009]; National Key Basic Research Program of China (973)[2007CB815303, 2009CB930703]; Xiamen University, China[2010121020]; National Found for Fostering Talents of Basic Science, China[J1030415]

Application of Copper Electrochemical Deposition for the Metallization of Micropores

National Natural Science Foundation of China[20873114, 20833005, 21021002]; National Key Basic Research Program of China[2009CB930703]

An analysis of the discipline development of energy chemistry in China

Energy Chemistry is a new interdisciplinary field of science that has arisen out of necessity to address the demands of the growing global energy crisis. This new field utilizes modern chemistry theories and methods to develop innovative and efficient energy technology and optimize energy harvesting, energy storage, and energy conversion methods. As one of Energy Science’s most important secondary disciplines, Energy Chemistry has ties to a number of scientific fields, including Physical Chemistry, Material Chemistry and Chemical Engineering. The way in which it integrates the disciplines of science and engineering is also quite unique and innovative, and has proven key in advancing the efficient utilization of energy as well as the development of new energy. Energy Science is likely to follow in the footsteps of Materials Science and Environmental Science, which have already become widely recognized in academia, industry, and society as first-class disciplines. It also has great potential to be included by ESI (Essential Science Indicators). Energy chemistry as a discipline hopes to construct the first comprehensive knowledge framework for Energy Science, and become the field′s leading secondary discipline. In this paper, we analyze the field of Energy Chemistry as a whole, including its limits, strategic potential, and characteristics. In order to clarify development goals and development strategy, this paper puts forward several suggestions concerning further development of Energy Chemistry. The discipline of Energy Chemistry is still in its infancy and does not yet have an established standard in many respects. We must take advantage of the institutional reforms currently being implemented to carefully steer the development of this new field. This means implementing top-level strategic planning, preparing the first set of Energy Chemistry textbooks, expediting vital research and experiments at partner universities, instigating the establishment of new energy sciences across the nation, and developing real-world applications for new energy technology.

Developing fast laboratory screening platform for sulfate dioxide in food by surface-enhanced Raman spectroscopy

The direct detection of sulphur dioxide has been realized in various food matrixes with high sensitivity and high selectivity, on the basis of the integration of the high energy resolution of the finger-print spectrum of surface-enhanced Raman spectroscopy and the universal but easy-on-going pretreatment procedure. The characteristic peak of sulphur dioxide at ~630 cm−1 was applied as the qualitative and quantitative standard, which displayed a lowest detectable concentration at the 1 mg kg−1 level for the spiked food samples. The key point of the high sensitivity and selectivity is the effective pretreatment born out of the standard distillation one, which has been improved in the three parts. (1) Using CaCO3 and Zeolite instead of N2 gas as the bubbling reagent. (2) Using oxalic acid as the acidic distillation solution to eliminate the hazards from acid volatilization, such as hydrochloric acid. (3) Using diluted sodium hydroxide solution as the absorption reagent instead of lead acetate solution to avoid the secondary pollution. With the three distinguished advantages of environment friendly, high sensitivity and free of matrix interference, the proposed method has great potential to replace the traditional ones for the fast screening of the illegal or abused sulphur dioxide in food.

Electrocrystallization of Cu-Sn Alloy on Copper Electrode Surface

National Natural Science Foundation of China [21021002]; National Key Basic Research Program of China (973) [2009CB930703]