The advancement in optical and electronic technologies plays a pivotal role in industrial production and scientific research, significantly driving the development of productivity, societal progress, and the improvement of human-being life. Diamond with its ultra-wide bandgap structure exhibits exceptional optoelectronic properties, such as high breakdown field, high carrier mobility, and intense radiation resistance, making it a promising material for high-power, high-efficiency, high-frequency, and harsh-environment optoelectronic devices. The development and application of synthetic and doping technologies are closely intertwined with its practical utilization.

The existing progress is achieved in the application of lasers, radiant detectors, and electronic devices. In the field of high-power Raman and Brillouin lasers, conventional Raman gain media (i.e., gases, crystals, and fibers) offer broad spectral transmission ranges, but suffer from a low thermal conductivity, leading to heat dissipate challenges under high-power operation and causing the degradation of beam quality. In contrast, diamond possesses the maximum thermal conductivity among crystalline materials, along with the largest Raman frequency shift, exceptionally high Raman gain coefficient, and remarkable Brillouin gain and frequency shift. These properties position diamond as an ideal candidate for high-power Brillouin and Raman lasers, enabling the maintenance of high beam quality under intense operating conditions, thereby representing a critical direction for advancing high-power laser technology. In radiation detection, conventional silicon detectors are incapable of withstanding high-intensity irradiation. In extreme environments, detection materials must exhibit superior radiation resistance, higher detection sensitivity, and broader detection ranges. Diamond, characterized by its ultra-wide bandgap, high carrier mobility, exceptional stability, and low dielectric constant, emerges as an ideal material. Diamond-based detectors can operate under harsh conditions such as high radiation intensity, high injection rates, and elevated temperatures, serving as key components in detection systems and providing novel solutions for extreme-environment applications. In the electronics sector, the exploration of post-Moore-era semiconductors becomes a research hotspot. Diamond, with its ultra-wide bandgap, high carrier saturation velocity, superior thermal conductivity, high carrier mobility, and high breakdown field strength, demonstrates a promising potential in electronic devices. Research on diamond-based diodes and transistors becomes popular.

As an emerging optoelectronic material, a comprehensive review of optoelectronic properties and applications of diamond holds a significant importance for its further development. This review briefly introduces diamond and its synthesis methods, discusses the critical role of synthetic technologies in optoelectronic applications, elaborates on the optoelectronic properties of diamond, with an overview of doping and color center, summarizes recent advances on ultra-wide bandgap diamond for radiation detect, high-power lasers, and electronic devices, and finally provides an outlook on the diamond-based optoelectronic applications.