NOVELTY - A photovoltaic device comprises first electrode, a second electrode, and an active material in electrical contact with the first and second electrodes, where the active material containing (i) oligothiophenes compound, and (ii) a second material which is either an electron donor material or an electron acceptor material, where the device generates an electrical potential upon the absorption of photons.    USE - As photovoltaic device (claimed) such as heterojunction and bilayer organic photovoltaic cells, organic photovoltaics (OPVs), hybrid solar cells and dye sensitized solar cells.    ADVANTAGE - The photovoltaic device comprises compound (I) having a lambda max of greater than or equal to 550 nm or greater than or equal to 560 nm, improved charge delocalization, and greater absorption of visible light than current oligothiophene-based material.    DETAILED DESCRIPTION - A photovoltaic device comprises first electrode, a second electrode, and an active material in electrical contact with the first and second electrodes, where the active material containing (i) oligothiophenes compound of formula (I), and (ii) a second material which is either an electron donor material or an electron acceptor material, where the device generates an electrical potential upon the absorption of photons.    EWG=electron withdrawing group or combination of groups (such as =C(CN)2 or group of formulae (i)-(iii));    R1 and R2=alkyl, aromatic or heteroaromatic groups;or    R1+R2=alkyl, aromatic or heteroaromatic group;    R3 and R4=alkyl, alkoxy or H;or    R3+R4=divalent alkyl group, divalent alkoxy or alkyldioxy group, heterocyclic, heteroaromatic or aromatic group linked or fused to the thiophene group;    R5=H or CN;    n=2-10;    R'x=1-8C alkyl, 1-8C perfluorinated alkyl, 3-8C cycloalkyl, aromatic, or heteroaromatic groups (all optionally substituted);    R'y=1-30C alkyl (where at least one carbon atom of the alkyl are optionally replaced with at least one O, S, NR6, carbonyl or thiocarbonyl), 3-8C cycloalkyl, 2-12C alkenyl (where at least one carbon atoms of the alkenyl are optionally replaced with at least one O, S, NR6, carbonyl or thiocarbonyl), 2-8C alkynyl (where at least one of the alkynyl are optionally replaced with at least one O, S, NR6, carbonyl or thiocarbonyl), 3-12C alkoxy, aromatic or heteroaromatic group (all optionally substituted);    R6=H or R'x;    R'u=H, alkyl, halo, perfluoroalkyl, carbonyl, carboxylic acid, alkoxy or hydroxyl;or    adjacent pair of R'u substituents+the carbon atoms to which they are attached=optionally substituted, optionally saturated aromatic ring;    m=4.    Provided that when EWG is =C(CN)2 then, R5 is H or CN. An INDEPENDENT CLAIM is included for new oligothiophenes compound of formula (II).    EWG'=electron withdrawing group or combination of groups (such as =C(CN)2, thiobarbituric acid of formula (ia) or isoxazolone of formula (iia));    R'1 and R'2=alkyl, aromatic or heteroaromatic groups;or    R'1+R'2=alkyl, aromatic or heteroaromatic group;    R'3 and R'4=alkyl, alkoxy or H;or    R'3+R'4=divalent alkyl group, divalent alkoxy or alkyldioxy group, heterocyclic, heteroaromatic or aromatic group linked or fused to the thiophene group;    R5'=H or CN;    n'=2-10.    Provided that:    (1) when EWG' is =C(CN)2 and R'3 and R'4 are H, then either (i) n' is 2 or 4-10, or (ii) R'1 and R'2 are each other than unsubstituted phenyl, or (iii) R'5 is CN;    (2) when EWG' is a thiobarbituric acid (ia) and R'3 and R'4 are H, then either: (i) n' is 3-10, or (ii) R'1 and R'2 are other than unsubstituted phenyl; and    (3) when EWG' is an isoxazolone (iia) and R'3 and R'4 are H, then either (i) n' is 3-10, or (ii) R'1 and R'2 are other than unsubstituted phenyl.