有机铝-SiO2型类气凝胶催化剂基材的制备工艺优化及其有机吸附性能研究

本文研究了有机铝-SiO2型类气凝胶催化剂基材制备的原料配比与催化剂基材成型度之间的关系,分析了该催化剂基材的结构特征,并探讨了不同配方制备的催化剂基材对有机物的吸附特征。结果表明,原料中对催化剂基材成型的主要影响因素为氯化铝与间苯三甲酸钠,次要影响因素为硅酸钠量。最佳成型配比为氯化铝2.41 g/100 mL (H2O),硅酸钠3.66 g/100 mL (H2O),间苯甲酸钠2.84 g/100 mL (H2O)。该催化剂基材呈现较明显的絮状、多孔的三维结构,并且对亚麻油的吸附量为3021 mg/g。另外,当间苯三甲酸钠浓度在2.1~2.7 g/100 mL (H2O)范围内,硅铝加入量在21~63 mL范围内生成的催化剂基材有较好的有机物吸收性能。The relationship between the ratio of raw materials and the molding degree of the Organic Al-SiO2 aerogel catalyst substrate was studied, and the structural characteristics of the catalyst substrate were analyzed, its additive property to linseed oil was studied. The results show that the main factors affecting the forming of catalyst substrate are aluminum chloride and sodium isophthalate, and the secondary factors are sodium silicate. The best molding ratio was aluminum chloride 2.41 g/100 mL (H2O), sodium silicate 3.66 g/100 mL (H2O), sodium isobenzoate 2.84 g/100 mL (H2O). The catalyst has a three-dimensional structure of flocculation and porosity, and the adsorption capacity of linseed oil is 3021 mg/g. In addition, when the concentration of sodium isophthalate is in the range of 2.1~2.7 g/100 mL (H2O) and the addition of Si-Al is in the range of 21 mL ~ 63 mL, the catalyst substrate has good organic absorption performance.

A mini review of NiFe-based materials as highly active oxygen evolution reaction electrocatalysts

Oxygen evolution reaction （OER） electrolysis, as an important reaction involved in water splitting and rechargeable metal-air batteries, has attracted increasing attention for clean energy generation and efficient energy storage. Nickel/iron （NiFe）-based compounds have been known as active OER catalysts since the last century, and renewed interest has been witnessed in recent years on developing advanced NiFe-based materials for better activity and stability. In this review, we present the early discovery and recent progress on NiFe-based OER electrocatalysts in terms of chemical properties, synthetic methodologies and catalytic performances. The advantages and disadvantages of each class of NiFe-based compounds are summarized, including NiFe alloys, electrodeposited films and layered double hydroxide nanoplates. Some mechanistic studies of the active phase of NiFe-based compounds are introduced and discussed to give insight into the nature of active catalytic sites, which could facilitate further improving NiFe based OER electrocatalysts. Finally, some applications of NiFe- based compounds for OER are described, including the development of an electrolyzer operating with a single AAA battery with voltage below 1.5 V and high performance rechargeable Zn-air batteries.

Improved performance and prolonged lifetime of titania-based materials: sequential use as adsorbent and photocatalyst

Lifetime is a key index in the evaluation of environmentally functional materials. Although it is well known that adsorption is the first step in photocatalysis, very little work has been done on the sequential use of materials as both adsorbents and photo- catalysts. In this work, two titania-based materials, TiO2 xerogel and TiO2 photocatalyst nanoparticles, were fabricated and evaluated as adsorbent and photocatalyst for the remediation of contaminated water with an azo dye, Acid Orange 7 （AO7）, as the modeling pollutant. The TiO2 xerogel showed a high adsorption capacity to AO7 （769 mg/g） and could be regenerated eas- ily with diluted NaOH solution （0.01 mol/L） for several cycles. The exhausted xerogel was calcined at 400 ℃ for 3 h and used as a photocatalyst for the degradation of AO7. Compared to the nanoparticles directly prepared from fresh TiO2 xerogel, the TiO2 nanoparticles from adsorption exhausted xerogel showed a much higher photocatalytic activity upon both UV and visible light irradiation. Thus the titania-based materials were endowed with improved performance as well as prolonged lifetime.