In the past decade, near-infrared (NIR) materials have
been developed
for sensor applications. NIR light-emitting diodes (LEDs) facilitate
roadside high-accuracy light detection and ranging, thus enhancing
driver safety and confidence. With advancements in wearable technology,
individuals, particularly young people, have exhibited a desire to
track their own health. Thus, nonintrusive light detection is likely
to become the mainstream of detection technology. However, short-wave
infrared (SWIR) phosphors are still under development. In the present
study, we explored materials with the potential for NIR to SWIR emission,
such as Eu2+ (ultrahigh crystal field), Cr3+ (six-fold coordination), and Ni2+ (six-fold coordination)
activators. Ni2+ is a suitable SWIR activator; however,
its blue light (450 nm) absorption ability is weak. The high-efficiency
transfer of energy from Eu2+ and Cr3+ to Ni2+ opens a new avenue for research on SWIR phosphors. We further
sorted the materials with high potentials for bioimaging and image
recognition applications. SWIR light can penetrate deep into biological
tissues and be used to observe the characteristic absorption frequencies
of various functional groups. Therefore, SWIR light is used in wearable
technology, clinical diagnosis, and chair-side dental checkup. With
the help of the artificial intelligence of things technology, image
recognition facilitates fast and nondestructive detection. In the
future, SWIR phosphors, which help avoid high temperature and working
noise, may replace traditional halogen lamps. Our findings reveal
the key factors influencing SWIR phosphors and provide insights into
the application design. The tunable emission of SWIR phosphors in
the 1000–1700 nm spectral range facilitates their widespread
applications.