Nickel oxide (NiO) has various applications in different fields. Here are some common uses of nickel oxide:

  1. Catalysis: Nickel oxide is widely used as a catalyst in several chemical reactions. It can promote oxidation and reduction reactions and is employed in processes such as hydrogenation, dehydrogenation, and methanation. Additionally, it finds applications in the production of ceramic materials and in the synthesis of various organic compounds.
  2. Batteries: Nickel oxide is a key component in rechargeable nickel-cadmium (NiCd) and nickel-metal hydride (NiMH) batteries. It serves as the positive electrode material (cathode), reacting with metal hydrides or cadmium to store and release electrical energy.
  3. Ceramic Industry: Due to its stability at high temperatures, nickel oxide is utilized in the production of ceramic glazes and pigments. It imparts specific colors, such as black or green, to ceramic products.
  4. Sensors: Nickel oxide is employed in gas sensing devices, particularly in detecting reducing gases like carbon monoxide (CO) and hydrogen (H2). The change in electrical properties of nickel oxide when exposed to these gases enables their detection.
  5. Electrochromic Devices: Nickel oxide thin films are utilized in electrochromic devices, which can change their optical properties (such as light transmission and reflection) in response to an applied electric field. These devices are used in smart windows, rear-view mirrors, and other applications where adjustable light transmission is desired.
  6. Fuel Cells: Nickel oxide is used as a catalyst in solid oxide fuel cells (SOFCs). It promotes the oxidation of hydrogen or hydrocarbons to produce electricity in these high-temperature fuel cell systems.
  7. Glass Industry: In the glass industry, nickel oxide is employed as a colorant to produce green glass, which finds application in decorative glassware, bottles, and architectural glass.