TECHNOLOGY FOCUS - ELECTRONICS - Preferred Components: In the organic LED, the negative electrode is aluminum, copper, silver or gold. The organic LED further comprises: a hole injection layer formed between the positive electrode and the light emitting layer; and a hole transporting layer formed between the positive electrode and the light emitting layer. In the organic solar cell: the substrate is a glass substrate; the positive electrode is indium tin oxide deposited on the glass substrate; and the negative electrode is a low work function metal.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The metal ions are ions of an alkali metal (preferred), alkaline earth metal or transition metal.    TECHNOLOGY FOCUS - POLYMERS - Preferred Components: The crown ether is of formula (-CH2-CH2-O(CH2CH2O)q). The conjugated polymer is of formula (-(Ar1)x-(Ar2)y-). The first repeating unit is substituted 9H-fluoren-2-yl compound of formula (I), substituted 9,9'-spirobi(fluorene)-7-yl compound of formula (II), substituted styrenyl compound of formula (III), substituted thiophenyl compound of formula (IV) or substituted phenyl compound of formula (V).q = 2-7;x, y = 0-1, where x+y = 1;Ar1, Ar2 = repeating unit comprising mono-, bicycle- and polycyclic aromatic groups, heterocyclic aromatic group, substituted aromatic group or substituted heterocyclic group, where one of the Ar1 and Ar2 is the first repeating unit;m = 0-4;n = 1-4;o = 1-2; andR1-R3 = crown ether-methylene-oxy-(1-22C alkylene), crown ether-methylene-oxy-(1-22C alkoxylene), crown ether-methylene-oxy-phenylene, crown ether-methylene-oxy-(7-28C alkylene) phenylene, crown ether-methylene-oxy-(7-28C alkoxylene) phenylene, crown ether-methylene-oxy-phenoxylene, crown ether-methylene-oxy-(7-28C alkylene) phenoxylene, crown ether-methylene-oxy-(7-28C alkoxylene) phenoxylene, crown ether-methylene-oxy-biphenylene, crown ether-methylene-oxy-(13-34C alkylene) biphenylene, crown ether-methylene-oxy-(13-34C alkoxylene) biphenylene, crown ether-methylene-oxy-biphenylene-oxy, crown ether-methylene-oxy-(13-34C alkylene) biphenylene-oxy or crown ether-methylene-oxy-(13-34C alkoxylene) biphenylene-oxy.The conjugated polymer is: a random copolymer, block copolymer or alternating copolymer; a homopolymer; copolymer or homopolymer having repeating units comprising one of (I)-(V); or polyfluorene having the first repeating unit comprising one of (I)-(V). The conjugated polymer comprises 1-100 mol.% of the first repeating unit. In the composite material, 1-100 mol.% of crown ethers are intercalated with metal ions. The hole-blocking polymer is: a conjugated or non-conjugated polymer having a large band gap; and polyethylene oxide. The polyethylene oxide has a weight average molecular weight of 50000-1000000 Daltons. EXAMPLE - No suitable example given.