The role of carbon capture, utilization, and storage for economic pathways that limit global warming to below 1.5°C.

The 2021 Intergovernmental Panel on Climate Change (IPCC) report, for the first time, stated that CO removal will be necessary to meet our climate goals. However, there is a cost to accomplish CO removal or mitigation that varies by source. Accordingly, a sensible strategy to prevent climate change begins by mitigating emission sources requiring the least energy and capital investment per ton of CO, such as new emitters and long-term stationary sources.

Optical simulation of ultimate performance enhancement in ultrathin Si solar cells by semiconductor nanocrystal energy transfer sensitization.

Energy transfer (ET) from nanocrystals (NCs) has shown potential to enhance the optoelectronic performance of ultrathin semiconductor devices such as ultrathin Si solar cells, but the experimental identification of optimal device geometries for maximizing the performance enhancement is highly challenging due to a large parameter space. Here, we have demonstrated a general theoretical framework combining transfer matrix method (TMM) simulations and energy transfer (ET) calculations to reveal critical device design guidelines for developing an efficient, NC-based ET sensitization of ultrathin Si solar cells, which are otherwise infeasible to identify experimentally. The results uncover that the ET-driven NC sensitization is highly effective in enhancing the short circuit current ( ) in sub-100 nm-thick Si layers, where, for example, the ET contribution can account for over 60% of the maximum achievable in 10 nm-thick ultrathin Si.

Enhanced photovoltaic performance of ultrathin Si solar cells via semiconductor nanocrystal sensitization: energy transfer vs. optical coupling effects.

Excitonic energy transfer (ET) offers exciting opportunities for advances in optoelectronic devices such as solar cells. While recent experimental attempts have demonstrated its potential in both organic and inorganic photovoltaics (PVs), what remains to be addressed is quantitative understanding of how different ET modes contribute to PV performance and how ET contribution is differentiated from the classical optical coupling (OC) effects. In this study, we implement an ET scheme using a PV device platform, comprising CdSe/ZnS nanocrystal energy donor and 500 nm-thick ultrathin Si acceptor layers, and present the quantitative mechanistic description of how different ET modes, distinguished from the OC effects, increase the light absorption and PV efficiency.

Sub-50-nm self-assembled nanotextures for enhanced broadband antireflection in silicon solar cells.

Materials providing broadband light antireflection have applications as highly transparent window coatings, military camouflage, and coatings for efficiently coupling light into solar cells and out of light-emitting diodes. In this work, densely packed silicon nanotextures with feature sizes smaller than 50 nm enhance the broadband antireflection compared with that predicted by their geometry alone. A significant fraction of the nanotexture volume comprises a surface layer whose optical properties differ substantially from those of the bulk, providing the key to improved performance.

Confinement-induced reduction in phase segregation and interchain disorder in bulk heterojunction films.

The effects of thin-film confinement on the material properties of ultrathin polymer (electron donor):fullerene (electron acceptor) bulk heterojunction films can be important for both fundamental understanding and device applications such as thin-film photovoltaics. We use variable angle spectroscopic ellipsometry and near edge X-ray absorption fine structure spectroscopy to measure the optical constants, donor-acceptor volume fraction profile, and the degree of interchain order as a function of the thickness of a poly(3-hexythiophene-2,5-diyl) and phenyl-C61-butyric acid methyl ester bulk heterojunction film. We find that as the thickness of the bulk heterojunction film is decreased from 200 nm to the thickness confinement regime (less than 20 nm), the vertical phase segregation gradient of the donor and acceptor phases becomes less pronounced.