Synthesis and ⁸³Kr NMR spectroscopy of Kr@C₆₀

Abstract

Synthesis of Kr@C60 is achieved by quantitative high-pressure encapsulation of the noble gas into an open-fullerene, and subsequent cage closure. Krypton is the largest noble gas entrapped in C60 using...

Atomic-Scale Time-Resolved Imaging of Krypton Dimers, Chains and Transition to a One-Dimensional Gas

“…Further, Figure 2c,d indicates no difference in the diameter of C 60 cages (∼0.7 nm), or spacing between adjacent cages (∼1.0 nm center-tocenter), when comparing (Kr@C 60 )@SWCNT and C 60 @ SWCNT. This reinforces the conclusion that carbon cages in Kr@C 60 and empty C 60 are effectively indistinguishable, supported by the small difference in 13 C NMR chemical shift previously determined by Hoffman et al 26 Figure 2e presents energy dispersive X-ray spectroscopy (EDS) data for a bundle of (Kr@C 60 )@SWCNT suspended over a hole in the TEM grid support film, confirming the presence of Kr at an abundance relative to carbon of ∼0.44 atomic % (at%). This is consistent with the anticipated abundance of Kr:C of 1:240 (i.e., ∼0.42 at %) for a single 1.4 nm diameter SWCNT fully filled with Kr@ C 60 (Figure S3).…”

“…This work aimed to investigate interatomic dynamics and bonding; hence, it was important to deliver target atoms into SWCNT as a stable compound with well-defined composition and structure. This was achieved by molecular surgery, whereby an orifice in the C 60 cage is opened, followed by Kr atom encapsulation and subsequent cage resealing, via a series of chemical transformations, yielding endohedral Kr@C 60 with >99% purity. , Kr@C 60 is the first stable compound of krypton, such that it can be heated to 550 °C without the loss of Kr and hence efficiently sublimed into SWCNT of average diameter ∼1.4 nm, thus delivering noble gas into the nanoscale cavities, forming (Kr@C 60 )@SWCNT as shown in Scheme .…”

Synthesis of Open‐Cage Fullerene Derivatives Containing Multiple Hydroxyl and Amino Groups on the Rim of the Orifice†

“…[ 1‐3,5 ] A number of noble gas atoms and small molecules have been inserted into the cavity of these open‐cage fullerenes. [ 6‐15 ] Recently, halide anions have also been successfully trapped into the cavity of a 19‐membered open‐cage fullerene derivative. [ 16 ]…”

Structural and chemical approaches to enhance the photo/electrocatalytic performance of carbon/g-C3N4 composite materials

“…In each C 60 molecule, 60 sp 2 hybridized carbon atoms are bond-connected each other to form a spherical structure with an outer diameter of 0.71 nm. 48,49 Being different, CDs are bond-connected by carbon atoms, with a certain ratio of sp 2 hybridized carbon atoms to sp 3 hybridized carbon atoms, to form quasi-spherical nanoparticles (2-10 nm in diameter and 0.5-3 nm in thickness). 16,48,50 According to their different carbon nucleus microstructure, CDs can be classified into graphene quantum dots (GQDs), carbon quantum dots (CQDs), carbon nanodots (CNDs) and carbonized polymer dots (CPDs).…”