EES Blog

Dye-sensitised solar cells (DSSCs) have been attracted increasing interest recently as an alternative to conventional silicon-based solar cells, owing to their relatively high conversion efficiencies and low manufacturing costs.

In DSSC devices, dye aggregation on the TiO₂ electrode is one of the most serious problems, which leads to a reduced device performance. Conventional solutions involve cumbersome optimisation processes and increased production costs, so a simple solution for the problem is required.

Scientists in Japan and China have reported an aggregation-free branch-type organic dye with a twisting pi-conjugate architecture. They compare it with an analogue dye possessing a planar molecular structure. The influences of deoxycholic acid co-adsorption are investigated, and it is found that the twisting dye has excellent potential as an aggregation-free dye.

Read the ‘HOT’ EES article hot off the press:

Aggregation-free branch-type organic dye with a twisted molecular architecture for dye-sensitized solar cells
Youhei Numata, Ashraful Islam, Han Chen and Liyuan Han
Energy Environ. Sci., 2012, Accepted Manuscript
DOI: 10.1039/C2EE22506A

Scientists in China and the US have demonstrated a thermoelectric material with excellent thermal and chemical stability up to high temperatures; it’s a promising material for converting wasted heat into electricity, they say.

The material is an oxyselenide – BiCuSeO. A high ZT ~1.1 at 923K in BiCuSeO system is achieved via Ba heavily doping and refining grain sizes (200~400 nm), which is higher than any thermoelectric oxides. Excellent thermal and chemical stability up to 923 K and high thermoelectric performance confirm that BiCuSeO system is promising for thermoelectric power generation applications.

Read the ‘HOT’ EES Communication:

High thermoelectric figure of merit ZT>1 in Ba heavily doped BiCuSeO oxyselenides
Li-Dong Zhao, Jing Li, Jiehe Sui, yanling pei, celine barreteau, David Berardan, Nita Dragoe, Wei Cai and Jiaqing He
Energy Environ. Sci., 2012, Accepted Manuscript
DOI: 10.1039/C2EE22622G

Scientists in the US have investigated the influence of a polymer’s crystallinity [P(VDF-TrFE)] on its function in ferroelectric photovoltaic devices by comparing crystalline and amorphous phases.

 The team’s results showed that the highly crystalline polymer film is needed for enhanced power conversion efficiency, because only crystalline P(VDF-TrFE) is ferroelectric.

 The method, they say, could be applied to many other devices, such as organic solar cells with low bandgap polymers, tandem solar cells, organic light emitting diodes, organic field effect transistors and organic bistable memories.

 Read the ‘HOT’ EES article today:

Understanding the effect of ferroelectric polarization on power conversion efficiency of organic photovoltaic devices
Y Yuan et al, Energy Environ. Sci., 2012, DOI: 10.1039/c2ee22098a

Scientists in China describe the synthesis of Ni–CaO–Al₂O₃ multifunctional catalysts from hydrotalcite-like precursors for sorption enhanced steam reforming of ethanol to produce hydrogen.

Read the EES ‘HOT’ paper hot off the press:

Sorption enhanced steam reforming of ethanol on Ni–CaO–Al₂O₃ multifunctional catalysts derived from hydrotalcite-like compounds
Gaowei Wu, Chengxi Zhang, Shuirong Li, Zhiqi Huang, Suli Yan, Shengping Wang, Xinbin Ma and Jinlong Gong
Energy Environ. Sci., 2012, DOI: 10.1039/C2EE21995F