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Ligand‐assisted perovskite nanoclusters (PNCs) have been synthesized using oleylamine and L‐ or D‐cysteine as confirmed based on their characteristic electronic absorption bands around 430 nm based on ultraviolet‐visible spectra. Circular dichroism (CD) spectra show distinct chiroptical bands in the 430–440 nm region, revealing the chirality of the PNCs. Interestingly, the sign of the CD signal is always negative, independent of the chirality for L‐ or D‐cystine. This 430–440 nm CD band is tentatively attributed to the formation of new chiral stereocenters within the PNCs with an uneven ratio of two enantiomers induced by the asymmetric liquid–liquid interface from the solvent and antisolvent used during synthesis. 

Mn²⁺doping of CsPbBr₃perovskite magic‐sized clusters (PMSCs) has been reported previously, where PMSCs with first excitonic absorption and photoluminescence (PL) around 425 nm were reported originally, followed by Mn²⁺‐doped PMSCs with host absorption and PL around 400 nm. There, the observed 25 nm blueshift was attributed to smaller PMSCs or the Cl⁻ions introduced by MnCl₂as dopant precursor. However, subsequent studies suggest that the 400 nm band may instead be due to ligand‐assisted metal halide molecular clusters (MHMCs), which lack the A component of perovskite. This raises the question whether the originally claimed Mn²⁺‐doped PMSCs are actually MHMCs. To unambiguously address this issue, Mn²⁺‐doped CH₃NH₃PbBr₃PMSCs were synthesized with PL at both 440 nm, attributed to the PMSC, and at 600 nm, attributed to Mn²⁺. Blueshifting of the host absorption and PL bands due to Cl⁻codoping is avoided by selecting MnBr₂as dopant precursor rather than MnCl₂. Dopant incorporation into PMSCs is further supported by PL excitation, time‐resolved PL, and electron paramagnetic resonance studies. This work provides direct and strong evidence of successful Mn²⁺doping in PMSCs. 

A solid-state synthesis of blue-emitting lead halide nanoclusters has been demonstrated for the first time. 

We have synthesized L-cysteine and oleylamine stabilized CsPbBr3 perovskite quantum dots (PQDs) and coupled them with gold nanoparticles (AuNPs). The PQDs and AuNPs, as well as their hybrid nanostructures (HNS), were characterized using UV–visible (UV–vis) and photoluminescence (PL) spectroscopy. The UV–vis spectra show absorption bands of the HNS at 503 and 520 nm, attributed mainly to PQDs and AuNPs, respectively. The PQDs show a strong excitonic PL band peaked at 513 nm from PQDs. The HR-TEM results show the formation of hybrid structures between PQDs and AuNPs, which is also supported by the PL quenching of the PQDs by the coupled AuNPs. Ultrafast dynamics of the exciton and charge carriers in the HNS and pristine PQD were studied using femtosecond transient absorption. Multiexponential fitting of the dynamic data revealed the existence of shallow and deep trap states in pristine PQDs and ultrafast electron transfer from PQDs to AuNPs in the HNS. A kinetic model was proposed to account for the key dynamic processes involved and to extract the time for electron transfer from PQDs to AuNPs in the HNS, found to be ∼2 ps. Dynamic processes in pristine PQDs are largely unchanged by HNS formation with AuNPs.