Atomically Precise Doping of Monomanganese Ion into Coreless Supertetrahedral Chalcogenide Nanocluster Inducing Unusual Red Shift in Mn²⁺ Emission

Abstract

We report a simple and yet effective method to introduce Mn(2+) ions into semiconducting nanoclusters with atomically precise control. Our method utilizes one type of micrometer-sized crystals, composed of well-defined isolated supertetrahedral chalcogenide nanoclusters (∼2 nm, [Cd6In28S52(SH)4]) whose core metal site is unoccupied in as-synthesized pristine form. This unique model structure with vacant core site makes it possible to achieve ordered distribution of Mn(2+) dopants, and at the same time effectively preclude the formation of Mn(2+) clusters in the host matrix. A two-step synthesis strategy is applied to realize an atomically precise doping of Mn(2+) ion into the core site of the nanoclusters, and to achieve uniform distribution of Mn(2+) dopants in the crystal lattice. The PL, X-ray photoelectron (XPS), as well as the electron paramagnetic resonance (EPR) spectra reveal the successful incorporation of Mn(2+) ion into the core site of the nanocluster. Different from the pristine host material with weak green emission (∼490 nm), the Mn(2+)-doped material shows a strong red emission (630 nm at room temperature and 654 nm at 30 K), which is significantly red-shifted relative to the orange emission (∼585 nm) observed in traditional Mn(2+)-doped II-VI semiconductors. Various experiments including extensive synthetic variations and PL dynamics have been performed to probe the mechanistic aspects of synthesis process and resultant unusual structural and PL properties. The quaternary semiconductor material reported here extends the emission window of Mn(2+)-doped II-VI semiconductor from yellow-orange to red, opening up new opportunities in applications involving photonic devices and bioimaging.

Tailored Near‐Infrared Photoemission in Fluoride Perovskites through Activator Aggregation and Super‐Exchange between Divalent Manganese Ions

“…This transition depends strongly on the crystal field of the ligands, what is most visible in the characteristic distinction between green luminescence that is typically associated with a tetrahedral coordination environment, IV Mn 2+ (i.e., lower ligand field strength), and orange or red luminescence from octahedral VI Mn 2+ (i.e., stronger ligand field) 6, 7. Between those two species, the overall luminescence properties, in particular, emission color and quantum efficiency, can be tailored by controlling the precipitation of the Mn 2+ activator 8, 9, 10…”

Supercubooctahedron (Cs6Cl)2Cs5[Ga15Ge9Se48] Exhibiting Both Cation and Anion Exchange

“…[1][2][3] Among them, large chalcogenide clusters are remarkable not only because of their beautiful structuralc hemistry of precisely defined size and composition, but also their properties, such as photocatalysis [4] and photoluminescence. [5] Intrinsically,t hese properties are associated with the secondary buildingu nits (SBUs), nanosized supertetrahedral clusters constructed from the primary buildingu nits, MQ 4 tetrahedra (M = metal, Q = chalcogen), through sharing apexes or edges. [6,7] To date, only three types of connectivity are known:s upertetrahedral clusters (Tn), penta-supertetrahedralc lusters (Pn), and capped supertetrahedral clusters (Cn).…”

“…[6,7] To date, only three types of connectivity are known:s upertetrahedral clusters (Tn), penta-supertetrahedralc lusters (Pn), and capped supertetrahedral clusters (Cn). [8] Some examples are T5-MnCd 6 In 28 S 52 (SH) 4 , [5] P2-Li 4 In 22 S 44 , [9] and C3,4-Cd 54 Se 32 (SPh) 48 (H 2 O) 4 . [10] The majority of these compounds contain heavy metals of the fifth period,s uch as In, Sn, or Cd, and those containing light period 4m etals are rare;t he several reported examples include Mn 6 (H 2 O) 3 (m 6 -Se)(GeSe 4 ) 4 , [11] Ge 4 S 10 (TEA-CuGS-SB1), [12] (C 4 NH 12 )Ga 10 S 18 , [13] and [(Zn 4 Ga 16 Se 33 ) 4 (Ga 2.4 Ge 1.6 Se 8 )]-(template) x , [14] of which the isolated 53-atom [Zn 4 Ga 16 Se 33 ]c luster is the largest till now.…”

“…Herein, we report an ovel type of supertetrahedral connectivity in the supercubooctahedron of (Cs 6 Cl) 2 Cs 5 [Ga 15 Ge 9 Se 48 ] (1), the largestc halcogenide cluster containing only period 4 elements. The supercubooctahedron is constructed from 72 skeleton atoms originating from eight M 3 Se 9 SBUs (M = disordered Ga/Ge;F igure 1).…”

Long-lived and Well-resolved Mn2+ Ion Emissions in CuInS-ZnS Quantum Dots

“…Luo et al achieved a high power conversion efficiency (PCE) of 5.38% in the QDSCs with Mn:CIS/CdS core–shell QDs, showing a 14.7% higher PEC than CIS/CdS counterparts22. With respect to state-of-the-art CIS based QDs, regardless of the fact that even the Mn 2+ dopants did have been incorporated, there still remain material- and fabrication- related obstacles in realizing high-performance CIS-based QDs with well-resolved Mn 2+ d-d emission and high efficiency as well as long lifetimes1528, which are important for their applications, e.g. , in bioimaging, opto/electronic devices.…”