Related Experiment Video
Updated: Feb 7, 2026

Author Spotlight: Assessing Brain Activity in Robotic-Assisted Lower Limb Rehabilitation Using fNIRS
Published on: June 7, 2024
Amorphous carbon layer: An effective assistant for realizing near-infrared-activated photocatalysis
Yuanyuan Zhang1, Lili Wang1, Xiumei Ma2
1Department of Chemistry and Pharmaceutical Science, Qingdao Agricultural University, PR China.
Abstract:
Carbon quantum dots (CQDs) were considered as desirable up-conversion luminescent materials. However, the reason leading to their up-conversion luminescence was not clear. In this paper, CQDs decorated ZnSn(OH)6 was successfully synthesized by facile in situ hydrothermal method. Under NIR light irradiation, ciprofloxacin degradation efficiency of sample was 37.4%. Subsequently, reasons for the up-conversion effect of CQDs were investigated to some extent. An amorphous carbon layer around CQDs was observed in composite (ZnSn(OH)6@CQDs@C) by HR-TEM and elemental mapping images. To study the effect of amorphous carbon layer on up-conversion performance, individual CQDs decorated ZnSn(OH)6 (ZnSn(OH)6@CQDs) was also fabricated by compositely coating. ZnSn(OH)6@CQDs had no up-conversion luminescence under 980 nm laser light excitation and its photocatalytic activity was negligible, implying amorphous carbon layer played a crucial role for realizing of up-conversion luminescence. A comparison of the FTIR spectra of two composites, ZnSn(OH)6@CQDs@C sample revealed greatly enhanced surface oxidation degree, polarity and hydrophilicity. Surface state of ZnSn(OH)6@CQDs@C composite was controlled by adjusting hydrothermal time, and the results confirmed that up-conversion performance had a close relationship with surface states of samples. This work could provide a new insight into understanding the up-conversion effect of CQDs.
Related Concept Videos
Factors Affecting Dissolution: Polymorphism, Amorphism and Pseudopolymorphism
Some polymorphic crystals possess lower aqueous solubility than their amorphous counterparts, leading to incomplete absorption. For instance, the oral suspension of Chloramphenicol, which...
The Carbon Cycle
Carbon Skeletons
Carbonation Shrinkage
The concrete's permeability is slightly reduced as calcium carbonate produced during the reaction fills its pores. Furthermore, its strength is slightly enhanced as the water released during the reaction...
Biological Effects of Radiation
Layers of the Epidermis
Stratum Basale
Stratum basale, also known as the stratum germinativum, is the deepest layer of the epidermis. It is composed of a single layer of actively dividing cells called basal cells or basal keratinocytes. These cells constantly undergo cell division to replenish the upper layers of the epidermis. Additionally, melanocytes, which...

