Dear friend Priyanka Dash

The Stokes shift is the difference between the energy of the absorbed and emitted light by a material. The Stokes shift of nitrogen-doped carbon quantum dots (NCQDs) with blue emission can be affected by various factors, including the quantum yield.

In general, the Stokes shift of NCQDs tends to increase with an increase in quantum yield. This is because higher quantum yield typically indicates a higher number of excited states, leading to a larger energy difference between the absorbed and emitted light, resulting in a larger Stokes shift.

However, the relationship between the Stokes shift and quantum yield is not always straightforward and can depend on other factors such as the size, shape, and surface chemistry of the NCQDs. Additionally, the specific experimental conditions, such as the excitation wavelength and temperature, can also influence the Stokes shift and quantum yield of NCQDs.

Overall, the relationship between the Stokes shift and quantum yield of NCQDs is complex and requires further investigation for a more precise understanding.

based in previous study >> Dong et al. (2019) found that the Stokes shift of blue-emitting N-CQDs increased from 20 nm to 40 nm as the quantum yield increased from 8% to 29%.

and other study : a study by Yu et al. (2019) observed that the Stokes shift of blue-emitting N-CQDs increased from 25 nm to 35 nm as the quantum yield increased from 12% to 37%.

It may be due to more energy transfer from the E.S to the G.S.

In case of N-CDs, E.S electrons recombine radiatively, because only few E.S electrons release heat and they interact with atmosphere and lose energy. So, the stoke shift is larger in NCDs.

Many studies demonstrated this shift in emission.