We present a new perylene sensitizer, ID176, for dye-sensitized solar cells (DSCs). The dye has the capability for very high photocurrents due to strong absorption from 400 to over 700 nm. Photocurrents of up to 9 mA cm -2 were achieved in solid-state DSCs employing the hole conductor 2,2′7,7′-tetrakis-(N,N-di-p-methoxyphenylamine)-9,9′-spirobifluorene (spiro-MeOTAD), with a conversion efficiency of 3.2%. In contrast, the sensitizer did not perform well in conjunction with liquid iodide/tri-iodide electrolytes, suggesting a difference in the injection and regeneration mechanisms in these two types of dye-sensitized solar cells.Dye-sensitized solar cells (DSCs) are the focus of much research due to their ability to convert sunlight to electricity at a low cost. 1 DSCs using a liquid electrolyte with the iodide/ tri-iodide redox couple have reached power conversion efficiencies of over 11%. 2 In comparison, solid-state DSCs (sDSCs) using the hole conductor 2,2′7,7′-tetrakis-(N,N-di-p-methoxyphenylamine)-9,9′-spirobifluorene (spiro-MeOTAD) have reached efficiencies of 4-5% with dyes showing much higher conversion efficiencies in liquid electrolyte DSCs. 3-6 Device performances of sDSCs are best when thin TiO 2 films (∼2 µm) are used due to limitations in pore filling and losses during charge transport. With ruthenium dyes, this limits the light harvesting as they have relatively low extinction coefficients. In comparison, organic dyes have much higher extinction coefficients but often also narrower absorption spectra. 7 Thus, to improve efficiencies, organic dyes with high extinction coefficients over a large range of the solar spectrum are needed. Here, we present a new perylene sensitizer, ID176, which absorbs strongly from 400 to above 700 nm. Intriguingly, this dye works well in solidstate DSCs but not in liquid electrolyte ones.Perylene dyes are promising candidates for DSC applications due to ease of synthesis, high stability, and broad absorption spectra. 8 However, previously published perylenes with good efficiencies in DSCs 9-11 were bound to TiO 2 through ringopening of an anhydride group, resulting in a significant spectral blue shift of their absorption spectra upon attachment to TiO 2 . In this work, we have replaced the anhydride anchor with a carboxylic acid anchor attached to a perylene monoimide, resulting in ID176 (Figure 1). The HOMO orbital of ID176 is mainly located on the bis(phenylamine) donor, while the LUMO orbital is mainly located on the perylene core. Thus, light absorption in this dye leads to internal charge transfer from the donor to the extremely strong imide acceptor. Figure 2 shows the absorption spectrum of ID176 in dichloromethane (DCM) solution and on TiO 2 . In solution, two absorption bands can be seen, one centered at 590 nm and a sideband at 480 nm. According to time-dependent DFT calculations, these bands correspond to a transition from the HOMO to the LUMO and to a transition from the HOMO-1 to the LUMO, respectively. Upon adsorption to TiO 2 , only a slight blue shift in ...

Crop-livestock-forest (CLFi) and crop-livestock (CLi) systems are among the most recent agricultural developments in Brazil, and aligned with the principles of cleaner production. Such integrated systems can provide at least three types of product from the same land area over a defined period. This paper presents a holistic sustainability evaluation using life cycle assessment to compare combinations of integrated and conventional systems in the Brazilian Cerrado region. The study assesses a comprehensive set of indicators in the three sustainability dimensions: environmental, economic, and social (socio-ecoefficiency). By prioritizing CLFi, the production area to meet the demand of grains, meat and energy for 500 Brazilians, from 2007 to 2014, reached 70 ha, while the conventional systems would need 420 ha to meet the same demand. This result shows that it is possible to increase production to meet the growing food global demand without the need of expanding the agricultural frontier, preserving the remaining forestland. CLFi combinations systems decreased 55% in climate change potential (2389 t of CO 2 equivalent), when compared to the conventional systems. It was also observed that the more integrated systems improved the quality of employment, promoted future generation investments in society, and decreased the total production costs in 54%, when compared to conventional systems. Therefore, intensification achieved through good practices such as association, rotation, and succession by an agroforestry system, optimization of inputs (including water, energy, fertilizers, and crop protection agents), land use, soil quality, biodiversity and social aspects.