The invention discloses a preparation method of 6N-grade high-purity
gallium oxide. The method comprises the following steps: directionally crystallizing and purifying a
raw material metal gallium to obtain high-purity
gallium; dissolving high-purity gallium in
nitric acid, evaporating and concentrating, and crystallizing at low temperature to obtain
gallium nitrate crystals; the preparation method comprises the following steps: dissolving
gallium nitrate crystals in
ultrapure water, and sequentially carrying out
ammonia water
neutralization and aging reaction to obtain a
gallium oxide precursor solution; and filtering, washing,
drying and calcining the
gallium oxide precursor solution in sequence to obtain the
gallium oxide photocatalyst. According to the method, directional
crystallization and
gallium nitrate recrystallization are effectively combined, so that the product purity is greatly improved, and the stability and continuity of product production are effectively ensured; according to the method,
electrolysis and replacement with high-purity gallium at the grade of 5N or above are not needed, stable preparation of the 6N-grade gallium
oxide can be achieved only through the 3-4N-grade
metal gallium, and the problems that in the prior art, high-purity gallium is high in cost, and stable and
continuous production is difficult are effectively solved.