The corrosion behavior and corrosion inhibition mechanism of carbon steel in concentrated LiBr solution at elevated temperature by LiNO
3, Li
2MoO
4 and LiNO
3/Li
2MoO
4 mixed inhibitors have been investigated. These inhibitors were effective in reducing corrosion, but pitting was likely to occur in the LiBr solution with LiNO
3 at some concentrations. With Li
2MoO
4/LiNO
3 initiation of pitting occurred as with LiNO
3, but its progression was prevented. The structure and composition of the surface films were analyzed by XRD, AES, SEM-EDX and XPS. A higher OH
- concentration in the surface films gave a lower corrosion rate. The surface films formed in the LiBr solutions with Li
2MoO
4 and LiNO
3/Li
2MoO
4 mixed inhibitors were composed of two layers, consisting of Li-Mo oxide including many OH
- ions and oxygen-deficient Fe oxide. On the other hand, with LiNO
3 inhibitor, Fe
3O
4 was formed. The relationships between the amount of corrosion and surface films structures were considered in terms of an interfacial ion-selective diffusion layer.
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