Converting absorbed photons into twice as many excitons

Science Daily  September 24, 2019 An international team of researchers (Japan, Finland) found that when light was exposed to the surface of a tetracene alkanethiol-modified gold nanocluster, they were able to convert singlet oxygen at a highly efficient conversion rate of 160%, far exceeding 100% conversion, in comparison to the number of absorbed photons. An increase in lifetime of about 10,000 times was achieved by greatly suppressing the rapid loss of excitation energy on the metal surface. These findings are expected to contribute to areas such as solar energy conversion, electronics, life sciences, and medical care in the future…read more. […]

After 40 Years of Searching, Scientists Identify The Key Flaw in Solar Panel Efficiency

Science Alert  June 8, 2019 Silicon solar cells containing boron and oxygen are one of the most rapidly growing forms of electricity generation. However, they suffer from significant degradation during the initial stages of use. Using ab initio modeling, an international team of researchers (UK, Portugal, Belarus, Australia) proposes structures of the BsO2 defect which match the experimental findings. They argue that the dominant recombination process associated with degradation is trap-assisted Auger recombination. This assignment is supported by the observation of above bandgap luminescence due to hot carriers resulting from the Auger process…read more. Open Access TECHNICAL ARTICLE

Using DNA templates to harness the sun’s energy

Science Daily  April 25, 2019 A team of researchers in the US (Arizona State University, University of New Mexico) reports significant progress in optimizing systems that mimic the first stage of photosynthesis. In previous the team demonstrated the utility of DNA to serve as a programmable template for aggregating dyes. To build upon these findings, they will use the photonic principles that underlie natural light harvesting complexes to construct programmable structures based on DNA self-assembly, which provides the flexible platform necessary for the design and development of complex molecular photonic systems. Using DNA architectures as a template, the researchers were able […]

Mystery of negative capacitance in perovskite solar cells solved

Eurekalert  April 5, 2019 An international team of researchers (Switzerland, Iran) found that the large perovskite capacitances are not classical capacitances in the sense of charge storage, but just appear as capacitances because of the cells’ slow response time. They found that the origin of the apparent capacitance is a slow modification of the current passing the contact of the solar cells, which is regulated by a slow accumulation of mobile ionic charge. A slowly increasing current appears like a negative capacitance in the impedance spectra. The work sheds light on the interaction between the photovoltaic effect in these devices […]

China Stumbles on Path to Solar Thermal Supremacy

IEEE Spectrum  February 14, 2019 Solar thermal plants are a potentially crucial power source for global grids as they add more wind and PV. However, the technology is comparatively costly and thus growing slowly relative to PV and wind. China’s program has been viewed as an opportunity to put solar thermal technology back on track, slash the cost of solar thermal power and catapult Chinese firms to the head of the global pack. In the final days of 2018 a 100-megawatt solar thermal generating station capable of running around-the-clock, 365-days-a-year was to be connected to the Northwest China regional power […]

China Is Reportedly Building a Solar Power Station in Space

Science Alert  February 2019 China has plans to launch a test facility before 2025, pursuing space-based clean energy showing that China is committed to its ongoing push towards using more renewable energy and asserting its place among global leaders in space. The plan is to have solar arrays in space capture light from the sun and then beam electricity down to a facility on Earth in the form of a microwave or a laser. If the launch goes well and the energy-transmitting beam works like it is supposed to, the Chinese scientists have plans to test and launch bigger and […]

Sun-soaking device turns water into superheated steam

MIT News  December 11, 2018 Researchers at MIT have built and demonstrated a solar-driven evaporation system. Top layer of the system is a metal ceramic composite and the bottom layer was coated with a material that easily and efficiently emits infrared heat. A layer of reticulated carbon foam is sandwiched between the two layers. It retains the sun’s incoming heat and can further heat up the steam rising back up through the foam. A small outlet tube allows steam to exit. The structure absorbs solar radiation and re-radiates infrared photons, which are directly absorbed by the water within a sub-100 μm penetration […]

Emissions-free energy system saves heat from the summer sun for winter

Science Daily  October 3, 2018 Building on their previous discovery of a molecule which could store solar energy, an international team of researchers (Sweden, Spain) has made it possible for a liquid form of the molecule made from carbon, hydrogen and nitrogen to store energy. It could be adapted for use in a solar energy system, MOST (Molecular Solar Thermal Energy Storage). The energy in the isomer can be stored for up to 18 years. The research group has developed a catalyst for controlling the release of the stored energy. MOST works in a circular manner – the liquid captures […]

Bacteria-powered solar cell converts light to energy, even under overcast skies

Science Daily  July 5, 2018 Researchers in Canada have genetically engineered E. coli to produce large amounts of lycopene that is particularly effective at harvesting light for conversion to energy. The pigment‐producing cells are coated with TiO2 nanoparticles and the mixture is applied to a glass surface. With the coated glass acting as an anode at one end of their cell, they generated a current density of 0.686 milliamps per square centimetre — an improvement on the 0.362 achieved by others in the field. According to the researchers the hybrid materials can be manufactured economically and sustainably. With sufficient optimization, […]

Promising new material has the right properties to capture solar energy, split water into hydrogen and oxygen

Phys.org  June 18, 2018 Using supercomputers to calculate the quantum energy states of four halide double perovskites, an international team of researchers (UK, USA – Cornell University) found that the double perovskites Cs2BiAgCl6 and Cs2BiAgBr6 are potentially promising materials for photo-catalytic water splitting. They would require controlling their surface termination to obtain energy levels appropriate for water splitting. The energy of the halogen P orbitals is found to control the conduction band level; therefore, the team proposes that mixed halides could be used to fine-tune the electronic affinity…read more. Open Access TECHNICAL ARTICLE