According to archaeological research, chemical chrome plating technology was already used on bronze weapons in China 2,200 years ago. The electrolytic chrome plating technology was first reported by German scholar Gerther in his doctoral dissertation in 1856. In the 1920s, Sargent and Fink further developed the hexavalent chromium plating technology using chromate as the electrolyte, which subsequently industrialized the chrome plating process. To date, this technology has a development history of nearly 100 years.

Today, the metal components of many household products and industrial goods are chrome-plated on the surface. This is because the chrome-plated layer not only serves an aesthetic purpose but, more importantly, enhances surface hardness and reduces corrosion of the base metal. Although there are currently various surface decoration and anti-corrosion technologies, chrome plating still occupies an important position. There are numerous chrome plating factories worldwide, and the demand for chrome plating remains strong.

Based on the type of electrolyte used, chrome plating processes are divided into hexavalent chromium processes and trivalent chromium processes. The hexavalent chromium (Cr(Ⅵ)) process, which has been developed to the present day, uses chromic anhydride (CrO₃) as the electrolyte, and concentrated chromic acid solution (CrO₃ + H₂SO₄) is prepared by adding sulfuric acid. The bath solution has extremely high acidity; chromium in chromic acid is reduced from Cr(Ⅵ) to Cr(Ⅲ), and finally to Cr(0). The electrode reaction equations at the cathode and anode during the chrome plating process are shown in Figure 1.