Novel near-ultraviolet-excited and thermally-stable blue-emitting phosphor for healthy WLED lighting

Development of thermally stable red-emitting lead-free double-perovskite phosphors with an internal PLQY approaching 100%

“…, incandescent and tungsten lamps), and have been extensively applied in our daily lives. 1–6 At present, researchers mainly tend to utilize phosphors coupled with blue or near-ultraviolet (NUV)/UV LED chips to fabricate phosphor-converted WLEDs (pc-WLEDs). 7,8 The approach based on blue LED chips is to utilize commercial YAG:Ce 3+ phosphors with broadband yellow emission, and it leads to a high correlated color temperature (CCT) and a low color rendering index (CRI) due to a lack of red emission.…”

“…White light-emitting diodes (WLEDs) as a new generation of solid-state lighting technology can achieve low energy consumption, high luminous efficiency, long service time, and some other advantages compared with traditional lighting sources (e.g., incandescent and tungsten lamps), and have been extensively applied in our daily lives. [1][2][3][4][5][6] At present, researchers mainly tend to utilize phosphors coupled with blue or near-ultraviolet (NUV)/UV LED chips to fabricate phosphor-converted WLEDs ( pc-WLEDs). 7,8 The approach based on blue LED chips is to utilize commercial YAG:Ce 3+ phosphors with broadband yellow emission, and it leads to a high correlated color temperature (CCT) and a low color rendering index (CRI) due to a lack of red emission.…”

Anionic Regulation toward Bi3+ Selective Occupation for Full-Spectrum White Light Emission

“…1−5 Among them, phosphor-converted white light-emitting diodes (pc-WLEDs) prepared from nearultraviolet (NUV) LED chips and tricolor phosphors have received much attention. 6,7 However, the coating technology used in fabricating WLED devices is quite complex, and the correlated color temperature (CCT) and color rendering index (CRI) of the emitted white light are difficult to control, which further limits their high-quality practical applications. Nowadays, the potential application of single-phase white phosphors in lighting and displays, which can effectively avoid the above problems, has attracted increased attention from researchers.…”

“…Compared with incandescent lighting, LED lighting is energy-saving, green, and portable, which is known as the 21st century “green light source”. − Among them, phosphor-converted white light-emitting diodes (pc-WLEDs) prepared from near-ultraviolet (NUV) LED chips and tricolor phosphors have received much attention. , However, the coating technology used in fabricating WLED devices is quite complex, and the correlated color temperature (CCT) and color rendering index (CRI) of the emitted white light are difficult to control, which further limits their high-quality practical applications. Nowadays, the potential application of single-phase white phosphors in lighting and displays, which can effectively avoid the above problems, has attracted increased attention from researchers. − Generally, most of the widely reported single-phase white light emission phosphors are based on multi-ion doping, e.g., Ca 2 P 2 O 7 :Eu 2+ , Mn 2+ ; Ca 3 Mg 3 (PO 4 ) 4 :Eu 2+ , Mn 2+ ; (Sr 3 ,Ca,Ba)­(PO 4 ) 3 Cl:Eu 2+ /Tb 3+ /Mn 2+ ; BaMg 2 Al 6 Si 9 O 30 :Eu 2+ /Tb 3+ /Mn 2+ ; Ca 2 SrAl 2 O 6 :Ce 3+ /Li + /Mn 2+ ; Mg 2 Y 8 (SiO 4 ) 6 O 2 :Ce 3+ /Mn 2+ /Tb 3+ ; KSrGd­(PO 4 ) 2 :Ce 3+ /Tb 3+ /Mn 2+ ; Ca 3 Y­(GaO) 3 (BO 3 ) 4 :Ce 3+ /Mn 2+ /Tb 3+ and Ca 4 Y 6 (SiO 4 ) 6 O:Ce 3+ / Mn 2+ /Tb 3+ . − However, differences in the decay lifetime, thermal quenching performances between activators, and the inevitable loss of energy transfer have led to poor color stability and a short service life for WLED devices …”

Enhanced effect of co-doping of Ln3+ on the luminescent properties of BaSiO3:Eu3+ red phosphors

“…Nevertheless, the commercial white LEDs, dominantly integrated the blue chips (InGaN) with yellow-emitting phosphors (Y 3 Al 5 O 12 :Ce 3+ ), exhibit a relatively low color rendering index (CRI) below 80 and a high color temperature (CCT) beyond 7000 K since the red components are absent [4]. In fact, the blue light would also be hazardous to human eyes, therefore, researchers have drawn more attention on new red phosphors or near-ultraviolet (n-UV) excited phosphors since the human eyes are not sensitive to n-UV light in range of 350 410 nm [5,6], expecting to achieve a high CRI, stable color coordinates, and low CCT [7]. In this case, the light of n-UV LEDs is mainly determined by the phosphors, of which the red one is the key and indispensable component to modulate the CRI.…”