• Energy Research

Gas-medium annealing simultaneously accomplished crystallization and surface passivation, contributing to high-quality perovskite films with much fewer defects from bulk to surface. A minimized energy loss of 0.29 eV was obtained for efficient PSCs.

A comprehensive review on the efficiency progress of inverted perovskite solar cells towards future development and commercialization.

Abstract The influence of the TiO2/electrode interface was investigated on electron transport properties at the interface and in TiO2 porous film in back contact dye-sensitized solar cells. Analysis of dye-sensitized solar cells (DSCs) with Ti and TCO indicated that electron transport properties at TiO2/Ti and TiO2/TCO interfaces are similar despite the former's lack of a ‘built-in potential’. The dependence of short circuit current density on TiO2 thickness indicated that TiO2 electron transport is not affected by ‘built-in potential’ or electrode structure. Electron transport thus appears similar in back contact dye-sensitized solar cells and DSCs. A back contact dye-sensitized solar cell fabricated with a Ti electrode and optimum TiO2 porous film showed a conversion efficiency of 7.8% with a metal mask under an air mass of 1.5 sunlight.

A universally useful idea for preparing high quality perovskite films is proposed by retarding the crystallization of PbI2, which make possible highly reproducible planar structured perovskite solar cells.

The recent research progress in film quality optimization strategies and the investigations of the film formation mechanism in all-inorganic CsPbX3 perovskite solar cells are systematically reviewed.

A large area perovskite film with less structural defects and a high material utilization ratio was formed by a continuous solution processing method, soft-cover deposition.

A hybrid interfacial layer of ultrathin NiO/meso-Al2O3with minimal optical/recombination losses, leads to solid performance improvement of inverted perovskite solar cells.

The efficiency of perovskite solar modules is limited by the difficulty in fabricating uniform and high-quality perovskite films. Now, a modified doctor blade method with a surfactant-controlled drying process has been shown to enable high-speed deposition of large-area and uniform perovskite films.

Five heteroleptic ruthenium complexes having differentβ-diketonato ligands, [Ru(tctpy)(dppd)(NCS)] (1), [Ru(tctpy)(pd)(NCS)] (2), [Ru(tctpy)(tdd)(NCS)] (3), [Ru(tctpy)(mepd)(NCS)] (4), and [Ru(tctpy)(tmhd)(NCS)] (5), where tctpy = 4,4′,4′′-tricarboxy-2,2′:6′,2′′-terpyridine, pd = pentane-2,4-dione, mepd = 3-methylpentane-2,4-dione, tmhd = 2,2,6,6-tetramethylheptane-3,5-dione, tdd = tridecane-6,8-dione, and dppd = 1,3-diphenylpropane-1,3-dione, were synthesized and characterized. These heteroleptic complexes exhibit a broad metal-to-ligand charge transfer absorption band over the whole visible range extending up to 950 nm. The low-energy absorption bands and theE (Ru3+/2+) oxidation potentials in these complexes could be tuned to about 15 nm and 110 mV, respectively, by choosing appropriateβ-diketonate ligands. Molecular orbital calculation of complex1shows that the HOMO is localized on the NCS ligand and the LUMO is localized on the tctpy ligand, which is anchored to the TiO2nanoparticles. Theβ-diketonato-ruthenium(II)-polypyridyl sensitizers, when anchored to nanocrystalline TiO2films for light to electrical energy conversion in regenerative photoelectrochemical cells, achieve efficient sensitization to TiO2electrodes with increasing activity in the order5<4<3≈2<1. Under standard AM 1.5 sunlight, the complex1yielded a short-circuit photocurrent density of 16.7 mA/cm2, an open-circuit voltage of 0.58 V, and a fill factor of 0.64, corresponding to an overall conversion efficiency of 6.2%. A systematic tuning of HOMO energy level shows that an efficient sensitizer should possess a ground-state redox potential value of >+.53 V versus SCE.