Executive Summary : | Hybrid metal halides have risen as a new class of material that show enhanced optoelectronic properties suitable for lighting applications (broadband white light emission, anti-counterfeiting, optical thermometry, X-ray detection). Metal halide hybrids are ionic compounds composed of organic cation and metal halide units. Connectivity of the metal halide units results in 3D, 2D, 1D, and 0D systems. Recently, doping of higher dimensional hybrids (3D, 2D,1D) has surfaced as an effective methodology to generate metal halide hybrids with tunable emission. However, doped higher dimensional variants are poor choice as host for generating multi-excitonic emission due to host-dopant electronic coupling in the networked structures. Naturally, 0D metal halide hybrids, with isolated metal halide units, are excellent choice as host material for doping/co-doping with dopant ions. Co-doping these 0D systems can tune/limit the extent of electronic interaction between the host-dopant and dopant-dopant that facilitates efficient multi-excitonic emission. In the absence of focused research reports on developing multi-excitonic emissive metal halide hybrids, the current proposal will devote experimental efforts towards synthesis and applications of low dimensional metal halide hybrid based multi-excitonic emissive materials utilizing doping/co-doping strategy. The current proposal will strive to develop chemical insights on utilization of appropriate components of the doped/co-doped 0D metal halide hybrids (choice of organic cation, metal halide host, metal halide dopants) towards realizing efficient multi excitonic emission spanning the visible and near-IR region. The choice of organic cations will serve as a synthetic handle to control the distance between the metal-halide units thereby tuning/limiting electronic coupling between the metal halide units of doped/co-doped low dimensional hybrids. Various metal halide units (Cd, In, Zn, Pb, Cu, Sn; X= Cl, Br) will be utilized to generate low dimensional host hybrids. These host hybrid halides will be doped/co-doped using various emissive metal/dopant ions such as transition metal ions, lanthanides, rare earths, and ns2 metal ions (Mn2+, Cu+, Yb3+, Er3+, Cr3+, Sb3+, Sn2+). The characteristics of the dopant will also play a crucial role in tuning the overall emission of such materials to achieve multi-excitonic emission. The proposed work is expected to shed new light on unraveling the design criteria/chemical insight towards development of multi-excitonic emissive materials through a rational doping/co-doping strategy utilizing low dimensional metal halide hybrids. The outcome of the proposal is expected to provide fundamental understanding and practical applications for broadband emission for WLEDs, optical thermometry, X-ray detection, and anti-counterfeiting agents. |