三硼酸钾的合成、表征及其振动光谱的研究

借助自行设计的沸腾反应器，采用碳酸钾和硼酸通过控制适宜的原料配比、反应温度和脱水温度合成出三硼酸钾。通过化学分析确定合成物分子式为一水三硼酸钾(KB₃O₅·H₂O)，通过粉末X射线衍射光谱(XRD)、傅里叶变换红外光谱(FTIR)、拉曼光谱(Raman)和热重分析(TG)等手段对其进行了表征，由粉末X射线衍射光谱分析确定合成物物质形态为无定形态，由傅里叶变换红外光谱和拉曼光谱分析确定合成物分子中存在三配位硼氧键B₍₃₎—O、四配位硼氧键B₍₄₎—O、羟基及三硼酸根离子，由热重分析确定合成物分子中存在能够失去一分子水的基团，并推出合成物三硼酸钾的结构式为KB₃O₄(OH)₂]。研究了合成物的振动光谱，包括红外光谱和拉曼光谱，考察了其中硼原子的主要存在形式三配位硼氧键B₍₃₎—O和四配位硼氧键B₍₄₎—O以及其他基团的振动情况，对振动频率进行了归属。

Synthesis, Characterization and Study on Vibration Spectra of Potassium Triborate

Potassium triborate was synthesized with potassium carbonate and boric acid by controlling suitable feed mixture ratio, reaction temperature and dehydration temperature in the self-designed boiling reactor. According to chemical analysis, the formula of the synthetics was monohydrate potassium triborate (KB3O5 x H2O). It's structure was characterized by XRD, FTIR, Raman and TG, and it was found by XRD analysis that the synthetics was amorphous solid. FTIR and Raman spectroscopy anal-ysis show that three coordination B(3) -O bond, four coordination B(4) -O bond, and hydroxy and triborate anions existed in the formula of the synthetics. Thermogravimetric (TG) analysis show that the groups which can lose mono-water existed in the formula of the synthetics, and structural formula of the synthetics was deduced as KB3O4 (OH)2]. Vibration spectra of the synthetics were studied, including FTIR and Raman spectroscopy. Vibration absorption peaks of some main groups of the synthetics were investigated, including three coordination B(3) -O bond and four coordination B(4) -O bond that are the main existing forms of boron atoms in the synthetics as well as other groups, and each vibration absorption peak was assigned.