(ShareCast News) - Graphene Nanochem posted a slightly wider first-half pre-tax loss as it continues to focus on higher-margin products.For the six months ended 30 June, the performance nanochemicals and advanced materials company reported a loss before tax of £3.7m compared with a £3.5m loss in the same period last year, as revenue fell to £7m from £20.4m.The company said it had anticipated the decline in revenues for the period in line with the overall rationalisation of its business to a suite of higher margin products and offerings within the performance chemicals and performance materials divisions as announced in June.Graphene progressively exited the capital-intensive low-margin fuel additives business during the period, as margins continued to decline with the collapse of oil prices.Chief executive officer Jespal Deol said: "This has been a period of further growth for the group, as we continue our focus on executing opportunities in higher margin products within the performance chemical & material businesses with growth potential that would contribute to a stronger bottom line for the group."We have made good progress despite the challenging market conditions and we will continue to focus on our strategy for growth in securing sales through our partnership model whilst continuing to manage our cost base to ensure sustained growth for the business."At 1350 BST, Graphene shares were down 10.8% at 13.82p.