In Situ FTIRS Studies of CO_2 Reduction on Thin Film Alloy El ectrodes

运用电化学循环伏安和原位FTIR反射光谱 ,研究CO2 的电催化还原过程。结果表明 ,纳米薄膜合金材料Sb Pb Pt/GC对CO2 还原具有较高的活性。还原产物以小分子羧酸和伯醇为主。The nanometer thin film alloy electrode (Sb-P b -Pt/GC)was prepared by electrochemical methods.Excellent catalytic effect was o bserved on these film alloy material in the electro-reduction of carbon dioxide (CO 2).The reduction can take place at potentials as high as -0 4 V.The oxid ation of reduced products of CO 2 on Sb-Pb-Pt/GC yielded current peaks at arr owd -0 08,0 2 and 0 3 V,while the oxidation of reduction products on a nm-P t/GC electrode gave rise a current peak near 0 4 V.The in situ FTIR spectroscop ic studies confirmed at a molecule level that the products of CO 2 reduction on Sb-Pb-Pt/GC are mainly organic acid and alcoholic compounds,while on a nm-Pt /GC electrode the production of CO 2 is mainly CO species.国家自然科学基金!(2 99730 35);; 福建省基金!(E991 0 0 0 3)资

Studies of surface alloy as high efficient electrocatalyst for glyoxylic acid synthesis

运用电化学方法，研制了三种表面合金（ＰｂＳｂＰｔ／ＧＣ，ＳｂＰｔ／ＧＣ，ＰｂＰｔ／ＧＣ）电催化剂，发现在草酸还原生成乙醛酸的电有机合成中这些表面合金电催化剂有较高的活性，其起始还原电位分别比在Ｐｂ阴极上（１．１Ｖ）提前了０．４８～０．７０Ｖ。这三种表面合金电催化剂的活性次序为：ＰｂＳｂＰｔ／ＧＣ＞ＳｂＰｔ／ＧＣ＞ＰｂＰｔ／ＧＣ。红外光谱结果表明，在这些表面合金电极上草酸还原产物主要为乙醛酸。作者联系地址：厦门大学化学系固体表面物理化学国家重点实验室Author's Address: Dept. of Chem., State Key Lab. for Phys. Chem. of the Solid Surf.,Inst. of Phys. Chem., Xiamen Univ., Xiamen 36100

In situ FTIRS studies of CO2 reduction on thin film alloy electrodes

The nanometer thin film alloy electrode (Sb-Pb-Pt/GC) was prepared by electrochemical methods. Excellent catalytic effect was observed on these film alloy material in the electro-reduction of carbon dioxide (CO2). The reduction can take place at potentials as high as -0.4 V. The oxidation of reduced products of CO2 on Sb-Pb-Pt/GC yielded current peaks at arrowd - 0.08, 0.2 and 0.3 V, while the oxidation of reduction products on a nm-Pt/GC electrode gave rise a current peak near 0.4 V. The in situ FTIR spectroscopic studies confirmed at a molecule level that the products of CO2 reduction on Sb-Pb-Pt/GC are mainly organic acid and alcoholic compounds, while on a nm-Pt/GC electrode the production of CO2 is mainly CO species

一种基于微电极的珊瑚共生体光补偿点测定方法探讨

珊瑚虫与虫黄藻互利共生形成共生体,虫黄藻通过光合作用为珊瑚虫提供重要的能量来源。珊瑚共生体的光补偿点可以较好地指示珊瑚的光适应性,是重要光合特性指标,但其测定方法鲜有报道。利用溶氧微电极结合光强可调节光源,以鹿角杯形珊瑚为实验材料,依据扩散平衡理论,建立了一种造礁石珊瑚的光补偿点的测定方法。实验结果表明珊瑚的扩散边界层溶氧浓度会快速响应光强变化。珊瑚扩散边界层溶氧浓度与光合有效辐射具有较好的相关性,且光强由高降低过程测得的相关系数更高。实验测得鹿角杯形珊瑚的光补偿点较低,为1.52μE/m~2/s,与喜阴植物的光补偿点相当。相对较低的光补偿点利于珊瑚栖居于水深范围更广的区域,有助于扩展珊瑚的生态位。溶氧微电极相关技术和方法在珊瑚光合作用研究中具有广泛的应用前景。中国科学院战略性先导科技专项A(XDA13020300)国家自然科学基金(41676163; 41406191; 41276113; 41276114)国家重点研发计划(2017YFC0506301,2018YFC1406500)广州市珠江科技新星(201806010017

In-Situ FTIR Spectroscopic Studies of Electro Oxidation of Ethanol in Alkaline Media at a nm-Pt/GC Electrode

运用电化学循环伏安和原位FTIR反射光谱研究了碱性介质中乙醇在nm Pt/GC电极上的氧化。结果表明 ,主要产物是CH3 COO-,仅存在少量乙醛 ,未检测到CO谱峰。与酸性介质中乙醇氧化的双途径机理不同 ,碱性介质中乙醇的氧化未经过解离吸附的中间步骤。The electro oxidation of ethanol on a nm Pt/GC electrode in alkaline solutions was investigated by using cyclic Voltammetry and in situ FTIR spectroscopy.The results demonstrated that the main product of ethanol oxidation was CH 3COO -,only small quantity of CH 3CHO was determined simultaneously.In contrast with the dual path reaction mechanism for the oxidation of ethanol in acid media,the oxidation of ethanol in alkaline media was revealed via the intermediate process of dissociative adsorption.国家自然科学基金项目!(2 98330 60 );; 国家教育部科学技术重点研究项目!(991 77)资

In-situ FTIR spectroscopic studies of electro oxidation of ethanol in alkaline media at a nm-Pt/GC electrode

The electro-oxidation of ethanol on a nm-Pt/GC electrode in alkaline solutions was investigated by using cyclic Voltammetry and in-situ FTIR spectroscopy. The results demonstrated that the main product of ethanol oxidation was CH3 COO-, only small quantity of CH3 CHO was determined simultaneously. In contrast with the dual path reaction mechanism for the oxidation of ethanol in acid media, the oxidation of ethanol in alkaline media was revealed via the intermediate process of dissociative adsorption

Study of Reduction Process of CO\-2 on Sb Pb Pt/GC Electrode

研制纳米薄膜合金电极 (Sb Pb Pt/GC电极 )用于二氧化碳电催化还原。运用循环伏安、电化学原位红外反射光谱和微电极技术对二氧化碳的电还原过程和还原产物进行研究。结果表明 :二氧化碳在此电极上的起始还原电位为 - 0 43V ,主要还原产物为有机羧酸。The reduction process of CO\-2 on Sb Pb Pt/GC electrode prepared by electrochemical co deposition method was studied with cyclic voltammetry and in situ FTIR spectroscopy.The results demonstrated that the prepared Sb Pb Pt/GC exhibited high activity for CO\-2 reduction. The onset potential of CO\-2 reduction was measured at -0 43 V and the main products of reduction were acid species as determined with in situ FTIR.福建省自然科学基金 !(E9910 0 0 3 );;教育部博士学科点专项基金 !(19990 3 840 3 )资助课

Study of Reduction of Oxalic Acid on Sb Pb Pt/GC Electrode Using CV and in situ FTIR

通过电化学方法和原位FTIR反射光谱等技术 ,对自行研制的碳载Sb Pb Pt纳米材料电极 ,在有机电合成中的性能进行了研究。结果表明 :该电极对草酸的加氢还原表现出很高的电催化活性 ,草酸的还原电位为 - 0 40V ,与铅阴极相比 ,正移约 6 0 0mV ;电化学原位FTIR反射光谱研究结果指出 ,草酸的还原产物主要为乙醛酸。Reduction of oxalic acid on electrode made of Sb Pb Pt nano material supported on glassy carbon was studied with cyclic voltammetry and in situ FTIR spectroscopy.The results demonstrated that the alloy thin film exhibited high electrocatalytic activity for oxalic acid reduction.The reduction potential was significantly reduced (about 600 mV) in comparison with a lead cathode used industrially for the reduction.Species of the main product identified by in situ FTIR spectroscopy were glyoxylic acid.This illustrated that the alloy film electrode exhibited excellent selectivity for oxalic acid reduction.福建省自然科学基金 !(E9910 0 0 3 );;国家自然科学基金! (2 983 3 0 60 )资助课

The Preparation and Characterization of Platinum Based Pb-Sb Surface Alloy Electrode

通过电化学方法，在玻碳载体表面制备以 Pt、 Pb、 Sb为主要成分的铂基 Pb-Sb表面合金电催化剂 .运用电化学循环伏安、石英晶体微天平（ EQCM）和扫描隧道显微镜（ STM）技术对催化剂电极进行表征 .结果表明：酸性溶液中在所制备的表面合金电极上，析氢起始电位负移至－ 0.45 V，表面合金的起始氧化电位为 0.15 V，其稳定性明显高于电催化还原中常用的铅、锑等金属电极 .通过 EQCM研究表面合金电极的形成过程，结合 STM观察和 XPS深度剖析，确定电催化剂表面是由粒度均匀的纳米颗粒构成的表面合金层 .The electrocatalysts of platinum based Pb-Sb surface alloy were prepared by electrochemical codeposition under cyclic voltammetric conditions. The structure and properties of these electrocatalysts were studied by techniques of cyclic voltammetry, electrochemical quartz crystal microbalance(EQCM), scanning tunneling microscopy(STM) and X-ray photoelectron spectroscopy(XPS). The results demonstrated that the hydrogen evolution on the prepared electrocatalyst was postponed to－ 0.45 V. i.e., 200 mV has been shifted negatively in comparison with hydrogen evolution at a platinum electrode. In addition,the oxidization of Pb and Sb components in surface alloy was positively shifted to above 0.15 V, which is much higher than the oxidization potential of Pb and Sb metal electrodes. The stability of surface alloy electrode is confirmed to be higher than Pb and Sb metal electrodes that were employed often in organic electrosynthesis. The process of formation of surface alloy was studied in situ by using an EQCM and ex situ by using a STM. The results have converged to illustrate that the surface alloy is constructed of nanoparticles with regular size of about 10 nanometers.The EQCM analysis and XPS depth profiling indicated that the surface alloy is formed on the top layer of a few nanometers in thickness of the Sb-Pb-Pt/GC electrode.国家自然科学基金!（ 29973035）;; 福建省自然科学基金!（ E9910003）&

Electrocatalytic Reduction of Oxalic Acid on Platinum Based Pb-Sb Surface Alloy Electrode

将 Sb-Pb-Pt/GC表面合金电极应用于草酸的电催化还原，发现所制备的催化剂电极具有较高的电催化活性，草酸还原的起始电位约－ 0.4 V，与通常使用的铅阴极相比，正移了大约 600 mV.电化学原位红外反射光谱研究，证实所研制的催化剂可在较低的过电位下还原草酸生成乙醛酸，并具有较好的选择性 .对于所研制的表面合金电催化剂的实际应用进行了探讨 .The platinum based Pb-Sb surface alloy supported on glassy carbon prepared by electrochemical codeposition has been applied to the reduction of oxalic acid. The results demonstrated that the surface alloy electrode exhibited a high activity, and reduced significantly the overpotential. In comparison with a lead cathode that was used usually in industry for the reduction of oxalic acid, the onset potential of oxalic acid reduction was shifted positively from-1.0 V on Pb to－ 0.4 V on the surface alloy electrode. The main product species were determined as glyoxylic acid by using in situ FTIR spectroscopy, illustrating that the surface alloy electrode exhibited also a high selectivity towards oxalic acid reduction.国家自然科学基金!（ 29973035）;; 福建省自然科学基金!（ E9910003）&