N,S-doped carbon quantum dots enhancing solar panel efficiency

Light Soaking No More: Quantum Dots Revolutionize Solar Cell Efficiency

Beau Callahan in Tech & Innovation September 2025 • 4 min read.

"N,S-doped carbon quantum dots offer a sustainable solution to enhance organic solar cell performance and eliminate the frustrating light soaking effect."

Organic solar cells (OSCs) hold immense promise as a sustainable energy solution, but they often face challenges that limit their performance. One of the most significant issues is the "light-soaking effect," where the cell's efficiency improves only after prolonged exposure to light. This inconsistency hinders real-world applications and overall reliability.

Researchers are actively exploring innovative materials to address these limitations. Among these, carbon quantum dots (CQDs) have emerged as a particularly promising avenue. CQDs are nanoscale carbon particles with unique optical and electronic properties, making them ideal for enhancing solar cell performance. A recent study published in ACS Applied Materials & Interfaces highlights a breakthrough in this area, focusing on nitrogen and sulfur-doped CQDs (N,S-CQDs).

This article delves into the exciting findings of this study, explaining how N,S-CQDs can be synthesized using a simple, sustainable method and how they work to eliminate the light-soaking effect, ultimately leading to more efficient and stable organic solar cells.

What are N,S-Doped Carbon Quantum Dots and Why Are They Important?

N,S-doped carbon quantum dots enhancing solar panel efficiency

Carbon quantum dots (CQDs) are tiny carbon-based nanoparticles, typically a few nanometers in diameter. What makes them special is their ability to absorb light and then re-emit it at different wavelengths, a process known as photoluminescence. Doping CQDs with other elements like nitrogen (N) and sulfur (S) further enhances their properties, tuning their electronic behavior and improving their ability to interact with light.

Here’s why N,S-doping is so crucial:

Enhanced Electron Donation: Sulfur, with its electron-rich nature and electronegativity similar to carbon, boosts the electron-donating capability of the CQDs.
Surface Passivation: The nitrogen and sulfur atoms help to passivate surface defects on other materials within the solar cell, leading to better overall performance.
Tunable Properties: Doping allows researchers to fine-tune the CQDs' optical and electronic properties, making them more effective in specific applications.

In essence, N,S-CQDs act as tiny performance-enhancing agents within the solar cell, optimizing light absorption and electron transport for improved efficiency.

The Future is Bright: Sustainable Solar with Quantum Dots

The development of N,S-doped carbon quantum dots offers a significant step forward in making organic solar cells a more viable and efficient renewable energy technology. By addressing the light-soaking effect and enhancing power conversion efficiency through a sustainable and cost-effective approach, this research paves the way for a brighter, greener future powered by the sun.

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

This article is based on research published under:

DOI-LINK: 10.1021/acsami.8b17128, Alternate LINK

Title: Synthesis Of N,S-Doped Carbon Quantum Dots For Use In Organic Solar Cells As The Zno Modifier To Eliminate The Light-Soaking Effect

Subject: General Materials Science

Journal: ACS Applied Materials & Interfaces

Publisher: American Chemical Society (ACS)

Authors: Yaling Wang, Lingpeng Yan, Guoqi Ji, Cheng Wang, Huimin Gu, Qun Luo, Qi Chen, Liwei Chen, Yongzhen Yang, Chang-Qi Ma, Xuguang Liu

Published: 2018-12-21

Everything You Need To Know

What is the 'light-soaking effect' in organic solar cells (OSCs), and why is eliminating it important?

Organic solar cells (OSCs) often suffer from the 'light-soaking effect,' where their efficiency only improves after prolonged exposure to light. This inconsistency makes them less reliable for real-world applications. N,S-doped carbon quantum dots (N,S-CQDs) offer a way to eliminate this issue, leading to more stable and efficient solar cells. Without addressing light soaking effect, OSCs can not be deployed in certain applications where immediate reliable power is required.

What are N,S-doped carbon quantum dots (N,S-CQDs), and what makes them unique compared to other materials?

N,S-doped carbon quantum dots (N,S-CQDs) are nanoscale carbon particles doped with nitrogen (N) and sulfur (S). This doping enhances their ability to absorb light and re-emit it at different wavelengths (photoluminescence), improving their interaction with light and overall solar cell performance. The N and S atoms passivate the surface defects in the solar cell. Doping allows researchers to fine-tune the CQDs' optical and electronic properties.

Why is doping carbon quantum dots (CQDs) with nitrogen and sulfur essential for enhancing solar cell performance?

Doping carbon quantum dots (CQDs) with nitrogen and sulfur is crucial for several reasons. Sulfur enhances electron donation due to its electron-rich nature. Both nitrogen and sulfur passivate surface defects, leading to better performance. Doping also allows fine-tuning of the CQDs' optical and electronic properties, making them more effective. This tunability ensures the N,S-CQDs can be optimized for specific solar cell applications, improving light absorption and electron transport.

How do N,S-doped carbon quantum dots (N,S-CQDs) function within organic solar cells (OSCs) to improve efficiency?

N,S-doped carbon quantum dots (N,S-CQDs) work within organic solar cells (OSCs) by optimizing light absorption and electron transport. They enhance electron donation, passivate surface defects, and allow for the fine-tuning of optical and electronic properties. By addressing the light-soaking effect and boosting power conversion efficiency, N,S-CQDs enhance the sustainability, cost-effectiveness, and long-term viability of solar energy technology.

What implications does the development of N,S-doped carbon quantum dots (N,S-CQDs) have for the future of solar energy and sustainability?

The development of N,S-doped carbon quantum dots (N,S-CQDs) represents a notable advancement, making organic solar cells (OSCs) a more viable and efficient renewable energy technology. Overcoming issues like the light-soaking effect addresses a key obstacle to deploying OSCs. Further research and development in CQD materials may lead to even greater efficiency and cost reductions in solar technology, accelerating the transition to sustainable energy sources.