Nature of peroxoborate species in aqueous solution: a study by boron-11 nuclear magnetic resonance and Raman spectroscopy

The 11B n.m.r. spectra of solutions of [B(OH)4]– or B(OH)3(0.01–4 mol dm–3) with H2O2(0.01–34 mol dm–3) have been studied from pH 14 to 4. A number of peroxoborates have been identified, in particular [B(O2H)n(OH)4 –n]–(n= 0–4) and polymeric species including [B2(O2)2(O2H)n(OH)4 –n]2–n= 0, 2, or 4). Raman spectra have been recorded for concentrated solutions {1–4 mol dm–3[B(OH)4]–, 1–12 mol dm–3 H2O2} and partial assignments proposed.