4Sb2O3 + 6Na[BH4] + 3H2SO4 + 6H2O → 8SbH3 + H3BO3 + 3Na2SO4
Antimony(III) oxide react with sodium tetrahydroxoborate(III), sulfuric acid and water to produce antimony(III) hydride, orthoboric acid and sodium sulfate. Sulfuric acid - diluted solution.