Surpassing the sensitivity limit and thermal quenching barrier in NIR luminescent thermometry in monazite BiPO4 concentrated with Nd
Year: 2026
Type: preprint
Abstract: Non-contact thermometry in the near infrared (NIR) region could enable minimally invasive thermal mapping in biological applications. Yet, existing probes often face trade-offs among sensitivity, brightness, and thermal stability. Here, we developed a single-ion Nd3+-based NIR thermometer, Bi1-xNdxPO4 (x = 0.20-0.40), via integrating several key structure-property considerations. The optimized composition Bi0.70Nd0.30PO4 in monazite structure , synthesized by a high-temperature solid-state reaction, delivers an ultra-high relative sensitivity of 6.62 %K-1 with temperature resolution of 0.29 K at 313 K, while exhibiting no measurable thermal quenching up to 673 K. Remarkably, its NIR-I emission is detectable even under an excitation power as low as 30 μW, highlighting efficient emission at ultra-low excitation. By integrating high sensitivity, thermal robustness, and low-power operation into a single Nd3+-emitting platform, this work establishes a materials design route toward practical NIR thermometry for biological and other demanding environments.
Source: ChemRxiv
Authors: Inderjeet Singh, Rajamani Nagarajan
Institution: University of Delhi
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7220833053