In recent years, the power conversion efficiency of perovskite solar cells has increased to reach over 20%. Finding an effective means of defect passivation is thought to be a promising route for bringing further increases in the power conversion efficiency and the open-circuit voltage (VOC) of perovskite solar cells. Here, we report the use of an organic halide salt phenethylammonium iodide (PEAI) on HC(NH2)2–CH3NH3 mixed perovskite films for surface defect passivation. We find that PEAI can form on the perovskite surface and results in higher-efficiency cells by reducing the defects and suppressing non-radiative recombination. As a result, planar perovskite solar cells with a certificated efficiency of 23.32% (quasi-steady state) are obtained. In addition, a VOC as high as 1.18 V is achieved at the absorption threshold of 1.53 eV, which is 94.4% of the Shockley–Queisser limit VOC (1.25 V). Planar perovskite solar cells that have been passivated using the organic halide salt phenethylammonium iodide are shown to have suppressed non-radiative recombination and operate with a certified power conversion efficiency of 23.3%.

Surface passivation of perovskite film for efficient solar cells

Although organic photovoltaic (OPV) cells have many advantages, their performance still lags far behind that of other photovoltaic platforms. A fundamental reason for their low performance is the low charge mobility of organic materials, leading to a limit on the active-layer thickness and efficient light absorption. In this work, guided by a semi-empirical model analysis and using the tandem cell strategy to overcome such issues, and taking advantage of the high diversity and easily tunable band structure of organic materials, a record and certified 17.29% power conversion efficiency for a two-terminal monolithic solution-processed tandem OPV is achieved.

https://science.sciencemag.org/content/sci/early/2018/08/08/science.aat2612.full.pdf

Organic and solution-processed tandem solar cells with 17.3% efficiency

The efficiency of silicon solar cells has a large influence on the cost of most photovoltaics panels. Here, researchers from Kaneka present a silicon heterojunction with interdigitated back contacts reaching an efficiency of 26.3% and provide a detailed loss analysis to guide further developments.

Silicon heterojunction solar cell with interdigitated back contacts for a photoconversion efficiency over 26

The efficiencies of perovskite solar cells have gone from single digits to a certified 22.1% in a few years' time. At this stage of their development, the key issues concern how to achieve further improvements in efficiency and long-term stability. We review recent developments in the quest to improve the current state of the art. Because photocurrents are near the theoretical maximum, our focus is on efforts to increase open-circuit voltage by means of improving charge-selective contacts and charge carrier lifetimes in perovskites via processes such as ion tailoring. The challenges associated with long-term perovskite solar cell device stability include the role of testing protocols, ionic movement affecting performance metrics over extended periods of time, and determination of the best ways to counteract degradation mechanisms.

http://science.sciencemag.org/content/sci/358/6364/739.full.pdf

Promises and challenges of perovskite solar cells

ZnS nanostructures: From synthesis to applications

An electrode layer formation step of forming an electrode layer including the first electrode and a removal-target body on a first main surface side of a photoelectric conversion part; an insulating layer formation step of forming an insulating layer so as to cover at least the removal-target body; an opening formation step of forming an opening in the insulating layer by utilizing the removal-target body; and a metal layer formation step of forming a metal layer on the electrode layer through the opening of the insulating layer by a plating method are performed in this order. In the opening formation step, at least a part of the removal-target body is removed by irradiation by a laser beam, so that the opening of the insulating layer is formed.

Solar cell, solar cell module, method for manufacturing solar cell, and method for manufacturing solar cell module

The present invention relates to a method of producing a crystalline silicon-based photoelectric conversion device sequentially having an intrinsic silicon-based layer, a p-type silicon-based layer and a transparent conductive layer on one side of a conductive monocrystalline silicon substrate, and sequentially having an intrinsic silicon-based layer, a n-type silicon-based layer and a transparent conductive layer on the other side of the conductive monocrystalline silicon substrate In the present invention, heat treatment is performed after at least one transparent conductive layer has been formed The heat treatment is performed at a temperature of less than 200°C under a hydrogen-containing atmosphere

Method of producing crystalline silicon-based photovoltaic cell

A solar cell is provided with an electrode layer on a photovoltaic conversion section including a crystalline silicon substrate Deposition of the electrode layer is performed by a deposit-up method with a substrate being mounted in such a manner that an opening edge portion of a mask plate having an opening is in contact with the substrate The opening edge portion of the mask plate has a tapered surface at a part that is in contact with first principal surface of the substrate, the tapered surface conforming to a deflection angle at a peripheral end of the substrate A solar cell having a large effective area can be prepared by suppressing deposition of electrode layer on mask-covered region due to penetration

Solar cell, method for manufacturing same, solar cell module, and method for manufacturing same

A solar cell of the present invention includes a collecting electrode on one main surface of a photoelectric conversion section. The collecting electrode includes first and second electroconductive layers in this order from the photoelectric conversion section side, and an insulating layer between the first and second electroconductive layers, the insulating layer having an opening section formed therein. The first electroconductive layer is covered with the insulating layer, contains a low-melting-point material, and is conductively connected with a part of the second electroconductive layer via the opening section. The surface roughness of the second electroconductive layer is preferably 1.0 μm to 10.0 μm. The second electroconductive layer is preferably formed by a plating method. In order to conductively connect the first and second electroconductive layers, annealing of the first electroconductive layer by heating is preferably performed prior to forming the second electroconductive layer.

Solar cell and method of manufacturing same, and solar cell module

PROBLEM TO BE SOLVED: To increase an open voltage, by suppressing carrier recombination on the surface of crystal silicon by providing an amorphous thin-film layer on the surface of crystal silicon in a method in which damage is less than before, in a crystal silicon solar cell. SOLUTION: The crystal silicon solar cell uses a one-conductivity type single-crystal silicon substrate of ≤250 μm in thickness, has a p-type silicon-system thin-film layer on one surface of the single-crystal silicon substrate, has an n-type silicon-system thin-film layer on the other surface of the single-crystal silicon substrate, includes transparent electrodes on the p-type and n-type silicon-system thin-film layers, and is provided with collector electrodes further on the transparent electrodes and protective layers further thereon. The crystal silicon solar cell is characterized in that a compound layer having amorphous aluminum oxide in major proportions is formed between the single-crystal silicon substrate and p-type silicon-system thin-film layer and/or between the single-crystal silicon substrate and n-type silicon-system thin-film layer. COPYRIGHT: (C)2011,JPO&INPIT

Daisuke Adachi

Papers

Solar cell, solar cell module, method for manufacturing solar cell, and method for manufacturing solar cell module

Method of producing crystalline silicon-based photovoltaic cell

Solar cell, method for manufacturing same, solar cell module, and method for manufacturing same

Solar cell and method of manufacturing same, and solar cell module

Crystal silicon solar cell