中文摘要：

将金电极在0.1mol.L-1氢氧化钠溶液中,在-0.8～0.8V电位范围内循环扫描8圈进行预处理。研究了甲醛在预处理金电极上的电化学行为,结果表明：甲醛在该电极上有一对氧化峰,峰电位分别为-0.45V和0.31V（vs.SCE）。据此提出了微分脉冲伏安法测定甲醛的方法。在电位-0.56V处,甲醛的氧化峰点与其浓度在1.0×10-6～1.0×10-3 mol.L-1范围内呈线性关系,方法的检出限（3S/N）为8.0×10-7 mol.L-1。应用该预处理金电极测定水样中甲醛,加标回收率在95.5%～103.7%之间,相对标准偏差（n=5）在3.9%～4.1%之间。

英文摘要：

Gold electrode was treated by scanning in the potential range of-0.8 to 0.8 V in 0.1mol·L-1 NaOH solution.The electrochemical behavior of formaldehyde at this pretreated Au electrode was studied.Two oxidation peaks of formaldehyde at the pretreated Au electrode,were observed at the potentials of-0.45 V and 0.31 V（vs.SCE）.Based on these findings,a sensitive method for determination of formaldehyde by differential pulse voltammetry was proposed.Linear relationship between values of peak current at-0.56 V and concentration of formaldehyde was obtained in the range of 1.0×10-6-1.0×10-3mol·L-1,with detection limit（3S/N） of 8.0×10-7mol·L-1.The proposed method was applied to the determination of formaldehyde in water samples,giving values of recovery and RSD′s（n=5） in ranges of 95.5%-103.7% and 3.9%-4.1%,respectively.